From f8d681efacb10c832d14e77c531646a56942963a Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=E5=AD=99=E5=B9=BF=E6=98=8E?= Date: Mon, 6 Jun 2022 13:54:06 +0800 Subject: [PATCH] * Fix bugs. --- doc/LICENSE.EN | 5 + lib/michelf/Michelf/Markdown.inc.php | 10 - lib/michelf/Michelf/Markdown.php | 1889 ---------------- lib/michelf/Michelf/MarkdownExtra.inc.php | 11 - lib/michelf/Michelf/MarkdownExtra.php | 1870 ---------------- lib/michelf/Michelf/MarkdownInterface.inc.php | 9 - lib/michelf/Michelf/MarkdownInterface.php | 38 - lib/michelf/michelf.class.php | 27 - lib/parsedownextraplugin/LICENSE.txt | 20 + lib/parsedownextraplugin/index.html | 0 lib/parsedownextraplugin/parsedown.php | 1992 +++++++++++++++++ lib/parsedownextraplugin/parsedownextra.php | 686 ++++++ .../parsedownextraplugin.class.php | 590 +++++ module/common/model.php | 8 +- 14 files changed, 3298 insertions(+), 3857 deletions(-) delete mode 100644 lib/michelf/Michelf/Markdown.inc.php delete mode 100644 lib/michelf/Michelf/Markdown.php delete mode 100644 lib/michelf/Michelf/MarkdownExtra.inc.php delete mode 100644 lib/michelf/Michelf/MarkdownExtra.php delete mode 100644 lib/michelf/Michelf/MarkdownInterface.inc.php delete mode 100644 lib/michelf/Michelf/MarkdownInterface.php delete mode 100644 lib/michelf/michelf.class.php create mode 100644 lib/parsedownextraplugin/LICENSE.txt create mode 100644 lib/parsedownextraplugin/index.html create mode 100644 lib/parsedownextraplugin/parsedown.php create mode 100644 lib/parsedownextraplugin/parsedownextra.php create mode 100644 lib/parsedownextraplugin/parsedownextraplugin.class.php diff --git a/doc/LICENSE.EN b/doc/LICENSE.EN index fd21d19cac..714eef045c 100644 --- a/doc/LICENSE.EN +++ b/doc/LICENSE.EN @@ -1,3 +1,8 @@ +ZenTao Project Management Software is licensed under the Z PUBLIC LICENSE (ZPL) 1.2 and the Affero General Public License (AGPL). +The ZPL is applied by default, or you can choose to use our software under the AGPL. + +----------------------------------------------------------------------------------------------------------------------------------------------------------------- + Z PUBLIC LICENSE 1.2 Authorization diff --git a/lib/michelf/Michelf/Markdown.inc.php b/lib/michelf/Michelf/Markdown.inc.php deleted file mode 100644 index e2bd3808e8..0000000000 --- a/lib/michelf/Michelf/Markdown.inc.php +++ /dev/null @@ -1,10 +0,0 @@ - - * @copyright 2004-2019 Michel Fortin - * @copyright (Original Markdown) 2004-2006 John Gruber - */ - -namespace Michelf; - -/** - * Markdown Parser Class - */ -class Markdown implements MarkdownInterface { - /** - * Define the package version - * @var string - */ - const MARKDOWNLIB_VERSION = "2.0"; - - /** - * Simple function interface - Initialize the parser and return the result - * of its transform method. This will work fine for derived classes too. - * - * @api - * - * @param string $text - * @return string - */ - public static function defaultTransform($text) { - // Take parser class on which this function was called. - $parser_class = static::class; - - // Try to take parser from the static parser list - static $parser_list; - $parser =& $parser_list[$parser_class]; - - // Create the parser it not already set - if (!$parser) { - $parser = new $parser_class; - } - - // Transform text using parser. - return $parser->transform($text); - } - - /** - * Configuration variables - */ - /** - * Change to ">" for HTML output. - */ - public $empty_element_suffix = " />"; - - /** - * The width of indentation of the output markup - */ - public $tab_width = 4; - - /** - * Change to `true` to disallow markup or entities. - */ - public $no_markup = false; - public $no_entities = false; - - - /** - * Change to `true` to enable line breaks on \n without two trailling spaces - * @var boolean - */ - public $hard_wrap = false; - - /** - * Predefined URLs and titles for reference links and images. - */ - public $predef_urls = array(); - public $predef_titles = array(); - - /** - * Optional filter function for URLs - * @var callable|null - */ - public $url_filter_func = null; - - /** - * Optional header id="" generation callback function. - * @var callable|null - */ - public $header_id_func = null; - - /** - * Optional function for converting code block content to HTML - * @var callable|null - */ - public $code_block_content_func = null; - - /** - * Optional function for converting code span content to HTML. - * @var callable|null - */ - public $code_span_content_func = null; - - /** - * Class attribute to toggle "enhanced ordered list" behaviour - * setting this to true will allow ordered lists to start from the index - * number that is defined first. - * - * For example: - * 2. List item two - * 3. List item three - * - * Becomes: - *
    - *
  1. List item two
    2. - *
  2. List item three
    3. - *
- */ - public $enhanced_ordered_list = false; - - /** - * Parser implementation - */ - /** - * Regex to match balanced [brackets]. - * Needed to insert a maximum bracked depth while converting to PHP. - */ - protected $nested_brackets_depth = 6; - protected $nested_brackets_re; - - protected $nested_url_parenthesis_depth = 4; - protected $nested_url_parenthesis_re; - - /** - * Table of hash values for escaped characters: - */ - protected $escape_chars = '\`*_{}[]()>#+-.!'; - protected $escape_chars_re; - - /** - * Constructor function. Initialize appropriate member variables. - * @return void - */ - public function __construct() { - $this->_initDetab(); - $this->prepareItalicsAndBold(); - - $this->nested_brackets_re = - str_repeat('(?>[^\[\]]+|\[', $this->nested_brackets_depth). - str_repeat('\])*', $this->nested_brackets_depth); - - $this->nested_url_parenthesis_re = - str_repeat('(?>[^()\s]+|\(', $this->nested_url_parenthesis_depth). - str_repeat('(?>\)))*', $this->nested_url_parenthesis_depth); - - $this->escape_chars_re = '['.preg_quote($this->escape_chars).']'; - - // Sort document, block, and span gamut in ascendent priority order. - asort($this->document_gamut); - asort($this->block_gamut); - asort($this->span_gamut); - } - - - /** - * Internal hashes used during transformation. - */ - protected $urls = array(); - protected $titles = array(); - protected $html_hashes = array(); - - /** - * Status flag to avoid invalid nesting. - */ - protected $in_anchor = false; - - /** - * Status flag to avoid invalid nesting. - */ - protected $in_emphasis_processing = false; - - /** - * Called before the transformation process starts to setup parser states. - * @return void - */ - protected function setup() { - // Clear global hashes. - $this->urls = $this->predef_urls; - $this->titles = $this->predef_titles; - $this->html_hashes = array(); - $this->in_anchor = false; - $this->in_emphasis_processing = false; - } - - /** - * Called after the transformation process to clear any variable which may - * be taking up memory unnecessarly. - * @return void - */ - protected function teardown() { - $this->urls = array(); - $this->titles = array(); - $this->html_hashes = array(); - } - - /** - * Main function. Performs some preprocessing on the input text and pass - * it through the document gamut. - * - * @api - * - * @param string $text - * @return string - */ - public function transform($text) { - $this->setup(); - - # Remove UTF-8 BOM and marker character in input, if present. - $text = preg_replace('{^\xEF\xBB\xBF|\x1A}', '', $text); - - # Standardize line endings: - # DOS to Unix and Mac to Unix - $text = preg_replace('{\r\n?}', "\n", $text); - - # Make sure $text ends with a couple of newlines: - $text .= "\n\n"; - - # Convert all tabs to spaces. - $text = $this->detab($text); - - # Turn block-level HTML blocks into hash entries - $text = $this->hashHTMLBlocks($text); - - # Strip any lines consisting only of spaces and tabs. - # This makes subsequent regexen easier to write, because we can - # match consecutive blank lines with /\n+/ instead of something - # contorted like /[ ]*\n+/ . - $text = preg_replace('/^[ ]+$/m', '', $text); - - # Run document gamut methods. - foreach ($this->document_gamut as $method => $priority) { - $text = $this->$method($text); - } - - $this->teardown(); - - return $text . "\n"; - } - - /** - * Define the document gamut - */ - protected $document_gamut = array( - // Strip link definitions, store in hashes. - "stripLinkDefinitions" => 20, - "runBasicBlockGamut" => 30, - ); - - /** - * Strips link definitions from text, stores the URLs and titles in - * hash references - * @param string $text - * @return string - */ - protected function stripLinkDefinitions($text) { - - $less_than_tab = $this->tab_width - 1; - - // Link defs are in the form: ^[id]: url "optional title" - $text = preg_replace_callback('{ - ^[ ]{0,'.$less_than_tab.'}\[(.+)\][ ]?: # id = $1 - [ ]* - \n? # maybe *one* newline - [ ]* - (?: - <(.+?)> # url = $2 - | - (\S+?) # url = $3 - ) - [ ]* - \n? # maybe one newline - [ ]* - (?: - (?<=\s) # lookbehind for whitespace - ["(] - (.*?) # title = $4 - [")] - [ ]* - )? # title is optional - (?:\n+|\Z) - }xm', - array($this, '_stripLinkDefinitions_callback'), - $text - ); - return $text; - } - - /** - * The callback to strip link definitions - * @param array $matches - * @return string - */ - protected function _stripLinkDefinitions_callback($matches) { - $link_id = strtolower($matches[1]); - $url = $matches[2] == '' ? $matches[3] : $matches[2]; - $this->urls[$link_id] = $url; - $this->titles[$link_id] =& $matches[4]; - return ''; // String that will replace the block - } - - /** - * Hashify HTML blocks - * @param string $text - * @return string - */ - protected function hashHTMLBlocks($text) { - if ($this->no_markup) { - return $text; - } - - $less_than_tab = $this->tab_width - 1; - - /** - * Hashify HTML blocks: - * - * We only want to do this for block-level HTML tags, such as headers, - * lists, and tables. That's because we still want to wrap

s around - * "paragraphs" that are wrapped in non-block-level tags, such as - * anchors, phrase emphasis, and spans. The list of tags we're looking - * for is hard-coded: - * - * * List "a" is made of tags which can be both inline or block-level. - * These will be treated block-level when the start tag is alone on - * its line, otherwise they're not matched here and will be taken as - * inline later. - * * List "b" is made of tags which are always block-level; - */ - $block_tags_a_re = 'ins|del'; - $block_tags_b_re = 'p|div|h[1-6]|blockquote|pre|table|dl|ol|ul|address|'. - 'script|noscript|style|form|fieldset|iframe|math|svg|'. - 'article|section|nav|aside|hgroup|header|footer|'. - 'figure|details|summary'; - - // Regular expression for the content of a block tag. - $nested_tags_level = 4; - $attr = ' - (?> # optional tag attributes - \s # starts with whitespace - (?> - [^>"/]+ # text outside quotes - | - /+(?!>) # slash not followed by ">" - | - "[^"]*" # text inside double quotes (tolerate ">") - | - \'[^\']*\' # text inside single quotes (tolerate ">") - )* - )? - '; - $content = - str_repeat(' - (?> - [^<]+ # content without tag - | - <\2 # nested opening tag - '.$attr.' # attributes - (?> - /> - | - >', $nested_tags_level). // end of opening tag - '.*?'. // last level nested tag content - str_repeat(' - # closing nested tag - ) - | - <(?!/\2\s*> # other tags with a different name - ) - )*', - $nested_tags_level); - $content2 = str_replace('\2', '\3', $content); - - /** - * First, look for nested blocks, e.g.: - *

- *
- * tags for inner block must be indented. - *
- *
- * - * The outermost tags must start at the left margin for this to match, - * and the inner nested divs must be indented. - * We need to do this before the next, more liberal match, because the - * next match will start at the first `
` and stop at the - * first `
`. - */ - $text = preg_replace_callback('{(?> - (?> - (?<=\n) # Starting on its own line - | # or - \A\n? # the at beginning of the doc - ) - ( # save in $1 - - # Match from `\n` to `\n`, handling nested tags - # in between. - - [ ]{0,'.$less_than_tab.'} - <('.$block_tags_b_re.')# start tag = $2 - '.$attr.'> # attributes followed by > and \n - '.$content.' # content, support nesting - # the matching end tag - [ ]* # trailing spaces/tabs - (?=\n+|\Z) # followed by a newline or end of document - - | # Special version for tags of group a. - - [ ]{0,'.$less_than_tab.'} - <('.$block_tags_a_re.')# start tag = $3 - '.$attr.'>[ ]*\n # attributes followed by > - '.$content2.' # content, support nesting - # the matching end tag - [ ]* # trailing spaces/tabs - (?=\n+|\Z) # followed by a newline or end of document - - | # Special case just for
. It was easier to make a special - # case than to make the other regex more complicated. - - [ ]{0,'.$less_than_tab.'} - <(hr) # start tag = $2 - '.$attr.' # attributes - /?> # the matching end tag - [ ]* - (?=\n{2,}|\Z) # followed by a blank line or end of document - - | # Special case for standalone HTML comments: - - [ ]{0,'.$less_than_tab.'} - (?s: - - ) - [ ]* - (?=\n{2,}|\Z) # followed by a blank line or end of document - - | # PHP and ASP-style processor instructions ( - ) - [ ]* - (?=\n{2,}|\Z) # followed by a blank line or end of document - - ) - )}Sxmi', - array($this, '_hashHTMLBlocks_callback'), - $text - ); - - return $text; - } - - /** - * The callback for hashing HTML blocks - * @param string $matches - * @return string - */ - protected function _hashHTMLBlocks_callback($matches) { - $text = $matches[1]; - $key = $this->hashBlock($text); - return "\n\n$key\n\n"; - } - - /** - * Called whenever a tag must be hashed when a function insert an atomic - * element in the text stream. Passing $text to through this function gives - * a unique text-token which will be reverted back when calling unhash. - * - * The $boundary argument specify what character should be used to surround - * the token. By convension, "B" is used for block elements that needs not - * to be wrapped into paragraph tags at the end, ":" is used for elements - * that are word separators and "X" is used in the general case. - * - * @param string $text - * @param string $boundary - * @return string - */ - protected function hashPart($text, $boundary = 'X') { - // Swap back any tag hash found in $text so we do not have to `unhash` - // multiple times at the end. - $text = $this->unhash($text); - - // Then hash the block. - static $i = 0; - $key = "$boundary\x1A" . ++$i . $boundary; - $this->html_hashes[$key] = $text; - return $key; // String that will replace the tag. - } - - /** - * Shortcut function for hashPart with block-level boundaries. - * @param string $text - * @return string - */ - protected function hashBlock($text) { - return $this->hashPart($text, 'B'); - } - - /** - * Define the block gamut - these are all the transformations that form - * block-level tags like paragraphs, headers, and list items. - */ - protected $block_gamut = array( - "doHeaders" => 10, - "doHorizontalRules" => 20, - "doLists" => 40, - "doCodeBlocks" => 50, - "doBlockQuotes" => 60, - ); - - /** - * Run block gamut tranformations. - * - * We need to escape raw HTML in Markdown source before doing anything - * else. This need to be done for each block, and not only at the - * begining in the Markdown function since hashed blocks can be part of - * list items and could have been indented. Indented blocks would have - * been seen as a code block in a previous pass of hashHTMLBlocks. - * - * @param string $text - * @return string - */ - protected function runBlockGamut($text) { - $text = $this->hashHTMLBlocks($text); - return $this->runBasicBlockGamut($text); - } - - /** - * Run block gamut tranformations, without hashing HTML blocks. This is - * useful when HTML blocks are known to be already hashed, like in the first - * whole-document pass. - * - * @param string $text - * @return string - */ - protected function runBasicBlockGamut($text) { - - foreach ($this->block_gamut as $method => $priority) { - $text = $this->$method($text); - } - - // Finally form paragraph and restore hashed blocks. - $text = $this->formParagraphs($text); - - return $text; - } - - /** - * Convert horizontal rules - * @param string $text - * @return string - */ - protected function doHorizontalRules($text) { - return preg_replace( - '{ - ^[ ]{0,3} # Leading space - ([-*_]) # $1: First marker - (?> # Repeated marker group - [ ]{0,2} # Zero, one, or two spaces. - \1 # Marker character - ){2,} # Group repeated at least twice - [ ]* # Tailing spaces - $ # End of line. - }mx', - "\n".$this->hashBlock("empty_element_suffix")."\n", - $text - ); - } - - /** - * These are all the transformations that occur *within* block-level - * tags like paragraphs, headers, and list items. - */ - protected $span_gamut = array( - // Process character escapes, code spans, and inline HTML - // in one shot. - "parseSpan" => -30, - // Process anchor and image tags. Images must come first, - // because ![foo][f] looks like an anchor. - "doImages" => 10, - "doAnchors" => 20, - // Make links out of things like `` - // Must come after doAnchors, because you can use < and > - // delimiters in inline links like [this](). - "doAutoLinks" => 30, - "encodeAmpsAndAngles" => 40, - "doItalicsAndBold" => 50, - "doHardBreaks" => 60, - ); - - /** - * Run span gamut transformations - * @param string $text - * @return string - */ - protected function runSpanGamut($text) { - foreach ($this->span_gamut as $method => $priority) { - $text = $this->$method($text); - } - - return $text; - } - - /** - * Do hard breaks - * @param string $text - * @return string - */ - protected function doHardBreaks($text) { - if ($this->hard_wrap) { - return preg_replace_callback('/ *\n/', - array($this, '_doHardBreaks_callback'), $text); - } else { - return preg_replace_callback('/ {2,}\n/', - array($this, '_doHardBreaks_callback'), $text); - } - } - - /** - * Trigger part hashing for the hard break (callback method) - * @param array $matches - * @return string - */ - protected function _doHardBreaks_callback($matches) { - return $this->hashPart("empty_element_suffix\n"); - } - - /** - * Turn Markdown link shortcuts into XHTML tags. - * @param string $text - * @return string - */ - protected function doAnchors($text) { - if ($this->in_anchor) { - return $text; - } - $this->in_anchor = true; - - // First, handle reference-style links: [link text] [id] - $text = preg_replace_callback('{ - ( # wrap whole match in $1 - \[ - ('.$this->nested_brackets_re.') # link text = $2 - \] - - [ ]? # one optional space - (?:\n[ ]*)? # one optional newline followed by spaces - - \[ - (.*?) # id = $3 - \] - ) - }xs', - array($this, '_doAnchors_reference_callback'), $text); - - // Next, inline-style links: [link text](url "optional title") - $text = preg_replace_callback('{ - ( # wrap whole match in $1 - \[ - ('.$this->nested_brackets_re.') # link text = $2 - \] - \( # literal paren - [ \n]* - (?: - <(.+?)> # href = $3 - | - ('.$this->nested_url_parenthesis_re.') # href = $4 - ) - [ \n]* - ( # $5 - ([\'"]) # quote char = $6 - (.*?) # Title = $7 - \6 # matching quote - [ \n]* # ignore any spaces/tabs between closing quote and ) - )? # title is optional - \) - ) - }xs', - array($this, '_doAnchors_inline_callback'), $text); - - // Last, handle reference-style shortcuts: [link text] - // These must come last in case you've also got [link text][1] - // or [link text](/foo) - $text = preg_replace_callback('{ - ( # wrap whole match in $1 - \[ - ([^\[\]]+) # link text = $2; can\'t contain [ or ] - \] - ) - }xs', - array($this, '_doAnchors_reference_callback'), $text); - - $this->in_anchor = false; - return $text; - } - - /** - * Callback method to parse referenced anchors - * @param array $matches - * @return string - */ - protected function _doAnchors_reference_callback($matches) { - $whole_match = $matches[1]; - $link_text = $matches[2]; - $link_id =& $matches[3]; - - if ($link_id == "") { - // for shortcut links like [this][] or [this]. - $link_id = $link_text; - } - - // lower-case and turn embedded newlines into spaces - $link_id = strtolower($link_id); - $link_id = preg_replace('{[ ]?\n}', ' ', $link_id); - - if (isset($this->urls[$link_id])) { - $url = $this->urls[$link_id]; - $url = $this->encodeURLAttribute($url); - - $result = "titles[$link_id] ) ) { - $title = $this->titles[$link_id]; - $title = $this->encodeAttribute($title); - $result .= " title=\"$title\""; - } - - $link_text = $this->runSpanGamut($link_text); - $result .= ">$link_text"; - $result = $this->hashPart($result); - } else { - $result = $whole_match; - } - return $result; - } - - /** - * Callback method to parse inline anchors - * @param array $matches - * @return string - */ - protected function _doAnchors_inline_callback($matches) { - $link_text = $this->runSpanGamut($matches[2]); - $url = $matches[3] === '' ? $matches[4] : $matches[3]; - $title =& $matches[7]; - - // If the URL was of the form it got caught by the HTML - // tag parser and hashed. Need to reverse the process before using - // the URL. - $unhashed = $this->unhash($url); - if ($unhashed !== $url) - $url = preg_replace('/^<(.*)>$/', '\1', $unhashed); - - $url = $this->encodeURLAttribute($url); - - $result = "encodeAttribute($title); - $result .= " title=\"$title\""; - } - - $link_text = $this->runSpanGamut($link_text); - $result .= ">$link_text"; - - return $this->hashPart($result); - } - - /** - * Turn Markdown image shortcuts into tags. - * @param string $text - * @return string - */ - protected function doImages($text) { - // First, handle reference-style labeled images: ![alt text][id] - $text = preg_replace_callback('{ - ( # wrap whole match in $1 - !\[ - ('.$this->nested_brackets_re.') # alt text = $2 - \] - - [ ]? # one optional space - (?:\n[ ]*)? # one optional newline followed by spaces - - \[ - (.*?) # id = $3 - \] - - ) - }xs', - array($this, '_doImages_reference_callback'), $text); - - // Next, handle inline images: ![alt text](url "optional title") - // Don't forget: encode * and _ - $text = preg_replace_callback('{ - ( # wrap whole match in $1 - !\[ - ('.$this->nested_brackets_re.') # alt text = $2 - \] - \s? # One optional whitespace character - \( # literal paren - [ \n]* - (?: - <(\S*)> # src url = $3 - | - ('.$this->nested_url_parenthesis_re.') # src url = $4 - ) - [ \n]* - ( # $5 - ([\'"]) # quote char = $6 - (.*?) # title = $7 - \6 # matching quote - [ \n]* - )? # title is optional - \) - ) - }xs', - array($this, '_doImages_inline_callback'), $text); - - return $text; - } - - /** - * Callback to parse references image tags - * @param array $matches - * @return string - */ - protected function _doImages_reference_callback($matches) { - $whole_match = $matches[1]; - $alt_text = $matches[2]; - $link_id = strtolower($matches[3]); - - if ($link_id == "") { - $link_id = strtolower($alt_text); // for shortcut links like ![this][]. - } - - $alt_text = $this->encodeAttribute($alt_text); - if (isset($this->urls[$link_id])) { - $url = $this->encodeURLAttribute($this->urls[$link_id]); - $result = "\"$alt_text\"";titles[$link_id])) { - $title = $this->titles[$link_id]; - $title = $this->encodeAttribute($title); - $result .= " title=\"$title\""; - } - $result .= $this->empty_element_suffix; - $result = $this->hashPart($result); - } else { - // If there's no such link ID, leave intact: - $result = $whole_match; - } - - return $result; - } - - /** - * Callback to parse inline image tags - * @param array $matches - * @return string - */ - protected function _doImages_inline_callback($matches) { - $whole_match = $matches[1]; - $alt_text = $matches[2]; - $url = $matches[3] == '' ? $matches[4] : $matches[3]; - $title =& $matches[7]; - - $alt_text = $this->encodeAttribute($alt_text); - $url = $this->encodeURLAttribute($url); - $result = "\"$alt_text\"";encodeAttribute($title); - $result .= " title=\"$title\""; // $title already quoted - } - $result .= $this->empty_element_suffix; - - return $this->hashPart($result); - } - - /** - * Parse Markdown heading elements to HTML - * @param string $text - * @return string - */ - protected function doHeaders($text) { - /** - * Setext-style headers: - * Header 1 - * ======== - * - * Header 2 - * -------- - */ - $text = preg_replace_callback('{ ^(.+?)[ ]*\n(=+|-+)[ ]*\n+ }mx', - array($this, '_doHeaders_callback_setext'), $text); - - /** - * atx-style headers: - * # Header 1 - * ## Header 2 - * ## Header 2 with closing hashes ## - * ... - * ###### Header 6 - */ - $text = preg_replace_callback('{ - ^(\#{1,6}) # $1 = string of #\'s - [ ]* - (.+?) # $2 = Header text - [ ]* - \#* # optional closing #\'s (not counted) - \n+ - }xm', - array($this, '_doHeaders_callback_atx'), $text); - - return $text; - } - - /** - * Setext header parsing callback - * @param array $matches - * @return string - */ - protected function _doHeaders_callback_setext($matches) { - // Terrible hack to check we haven't found an empty list item. - if ($matches[2] == '-' && preg_match('{^-(?: |$)}', $matches[1])) { - return $matches[0]; - } - - $level = $matches[2][0] == '=' ? 1 : 2; - - // ID attribute generation - $idAtt = $this->_generateIdFromHeaderValue($matches[1]); - - $block = "".$this->runSpanGamut($matches[1]).""; - return "\n" . $this->hashBlock($block) . "\n\n"; - } - - /** - * ATX header parsing callback - * @param array $matches - * @return string - */ - protected function _doHeaders_callback_atx($matches) { - // ID attribute generation - $idAtt = $this->_generateIdFromHeaderValue($matches[2]); - - $level = strlen($matches[1]); - $block = "".$this->runSpanGamut($matches[2]).""; - return "\n" . $this->hashBlock($block) . "\n\n"; - } - - /** - * If a header_id_func property is set, we can use it to automatically - * generate an id attribute. - * - * This method returns a string in the form id="foo", or an empty string - * otherwise. - * @param string $headerValue - * @return string - */ - protected function _generateIdFromHeaderValue($headerValue) { - if (!is_callable($this->header_id_func)) { - return ""; - } - - $idValue = call_user_func($this->header_id_func, $headerValue); - if (!$idValue) { - return ""; - } - - return ' id="' . $this->encodeAttribute($idValue) . '"'; - } - - /** - * Form HTML ordered (numbered) and unordered (bulleted) lists. - * @param string $text - * @return string - */ - protected function doLists($text) { - $less_than_tab = $this->tab_width - 1; - - // Re-usable patterns to match list item bullets and number markers: - $marker_ul_re = '[*+-]'; - $marker_ol_re = '\d+[\.]'; - - $markers_relist = array( - $marker_ul_re => $marker_ol_re, - $marker_ol_re => $marker_ul_re, - ); - - foreach ($markers_relist as $marker_re => $other_marker_re) { - // Re-usable pattern to match any entirel ul or ol list: - $whole_list_re = ' - ( # $1 = whole list - ( # $2 - ([ ]{0,'.$less_than_tab.'}) # $3 = number of spaces - ('.$marker_re.') # $4 = first list item marker - [ ]+ - ) - (?s:.+?) - ( # $5 - \z - | - \n{2,} - (?=\S) - (?! # Negative lookahead for another list item marker - [ ]* - '.$marker_re.'[ ]+ - ) - | - (?= # Lookahead for another kind of list - \n - \3 # Must have the same indentation - '.$other_marker_re.'[ ]+ - ) - ) - ) - '; // mx - - // We use a different prefix before nested lists than top-level lists. - //See extended comment in _ProcessListItems(). - - if ($this->list_level) { - $text = preg_replace_callback('{ - ^ - '.$whole_list_re.' - }mx', - array($this, '_doLists_callback'), $text); - } else { - $text = preg_replace_callback('{ - (?:(?<=\n)\n|\A\n?) # Must eat the newline - '.$whole_list_re.' - }mx', - array($this, '_doLists_callback'), $text); - } - } - - return $text; - } - - /** - * List parsing callback - * @param array $matches - * @return string - */ - protected function _doLists_callback($matches) { - // Re-usable patterns to match list item bullets and number markers: - $marker_ul_re = '[*+-]'; - $marker_ol_re = '\d+[\.]'; - $marker_any_re = "(?:$marker_ul_re|$marker_ol_re)"; - $marker_ol_start_re = '[0-9]+'; - - $list = $matches[1]; - $list_type = preg_match("/$marker_ul_re/", $matches[4]) ? "ul" : "ol"; - - $marker_any_re = ( $list_type == "ul" ? $marker_ul_re : $marker_ol_re ); - - $list .= "\n"; - $result = $this->processListItems($list, $marker_any_re); - - $ol_start = 1; - if ($this->enhanced_ordered_list) { - // Get the start number for ordered list. - if ($list_type == 'ol') { - $ol_start_array = array(); - $ol_start_check = preg_match("/$marker_ol_start_re/", $matches[4], $ol_start_array); - if ($ol_start_check){ - $ol_start = $ol_start_array[0]; - } - } - } - - if ($ol_start > 1 && $list_type == 'ol'){ - $result = $this->hashBlock("<$list_type start=\"$ol_start\">\n" . $result . ""); - } else { - $result = $this->hashBlock("<$list_type>\n" . $result . ""); - } - return "\n". $result ."\n\n"; - } - - /** - * Nesting tracker for list levels - */ - protected $list_level = 0; - - /** - * Process the contents of a single ordered or unordered list, splitting it - * into individual list items. - * @param string $list_str - * @param string $marker_any_re - * @return string - */ - protected function processListItems($list_str, $marker_any_re) { - /** - * The $this->list_level global keeps track of when we're inside a list. - * Each time we enter a list, we increment it; when we leave a list, - * we decrement. If it's zero, we're not in a list anymore. - * - * We do this because when we're not inside a list, we want to treat - * something like this: - * - * I recommend upgrading to version - * 8. Oops, now this line is treated - * as a sub-list. - * - * As a single paragraph, despite the fact that the second line starts - * with a digit-period-space sequence. - * - * Whereas when we're inside a list (or sub-list), that line will be - * treated as the start of a sub-list. What a kludge, huh? This is - * an aspect of Markdown's syntax that's hard to parse perfectly - * without resorting to mind-reading. Perhaps the solution is to - * change the syntax rules such that sub-lists must start with a - * starting cardinal number; e.g. "1." or "a.". - */ - $this->list_level++; - - // Trim trailing blank lines: - $list_str = preg_replace("/\n{2,}\\z/", "\n", $list_str); - - $list_str = preg_replace_callback('{ - (\n)? # leading line = $1 - (^[ ]*) # leading whitespace = $2 - ('.$marker_any_re.' # list marker and space = $3 - (?:[ ]+|(?=\n)) # space only required if item is not empty - ) - ((?s:.*?)) # list item text = $4 - (?:(\n+(?=\n))|\n) # tailing blank line = $5 - (?= \n* (\z | \2 ('.$marker_any_re.') (?:[ ]+|(?=\n)))) - }xm', - array($this, '_processListItems_callback'), $list_str); - - $this->list_level--; - return $list_str; - } - - /** - * List item parsing callback - * @param array $matches - * @return string - */ - protected function _processListItems_callback($matches) { - $item = $matches[4]; - $leading_line =& $matches[1]; - $leading_space =& $matches[2]; - $marker_space = $matches[3]; - $tailing_blank_line =& $matches[5]; - - if ($leading_line || $tailing_blank_line || - preg_match('/\n{2,}/', $item)) - { - // Replace marker with the appropriate whitespace indentation - $item = $leading_space . str_repeat(' ', strlen($marker_space)) . $item; - $item = $this->runBlockGamut($this->outdent($item)."\n"); - } else { - // Recursion for sub-lists: - $item = $this->doLists($this->outdent($item)); - $item = $this->formParagraphs($item, false); - } - - return "
  • " . $item . "
    • \n"; - } - - /** - * Process Markdown `
    ` blocks.
-	 * @param  string $text
-	 * @return string
-	 */
-	protected function doCodeBlocks($text) {
-		$text = preg_replace_callback('{
-				(?:\n\n|\A\n?)
-				(	            # $1 = the code block -- one or more lines, starting with a space/tab
-				  (?>
-					[ ]{'.$this->tab_width.'}  # Lines must start with a tab or a tab-width of spaces
-					.*\n+
-				  )+
-				)
-				((?=^[ ]{0,'.$this->tab_width.'}\S)|\Z)	# Lookahead for non-space at line-start, or end of doc
-			}xm',
-			array($this, '_doCodeBlocks_callback'), $text);
-
-		return $text;
-	}
-
-	/**
-	 * Code block parsing callback
-	 * @param  array $matches
-	 * @return string
-	 */
-	protected function _doCodeBlocks_callback($matches) {
-		$codeblock = $matches[1];
-
-		$codeblock = $this->outdent($codeblock);
-		if (is_callable($this->code_block_content_func)) {
-			$codeblock = call_user_func($this->code_block_content_func, $codeblock, "");
-		} else {
-			$codeblock = htmlspecialchars($codeblock, ENT_NOQUOTES);
-		}
-
-		# trim leading newlines and trailing newlines
-		$codeblock = preg_replace('/\A\n+|\n+\z/', '', $codeblock);
-
-		$codeblock = "
    $codeblock\n
    ";
-		return "\n\n" . $this->hashBlock($codeblock) . "\n\n";
-	}
-
-	/**
-	 * Create a code span markup for $code. Called from handleSpanToken.
-	 * @param  string $code
-	 * @return string
-	 */
-	protected function makeCodeSpan($code) {
-		if (is_callable($this->code_span_content_func)) {
-			$code = call_user_func($this->code_span_content_func, $code);
-		} else {
-			$code = htmlspecialchars(trim($code), ENT_NOQUOTES);
-		}
-		return $this->hashPart("$code");
-	}
-
-	/**
-	 * Define the emphasis operators with their regex matches
-	 * @var array
-	 */
-	protected $em_relist = array(
-		''  => '(?:(? '(? '(? '(?:(? '(? '(? '(?:(? '(? '(?em_relist as $em => $em_re) {
-			foreach ($this->strong_relist as $strong => $strong_re) {
-				// Construct list of allowed token expressions.
-				$token_relist = array();
-				if (isset($this->em_strong_relist["$em$strong"])) {
-					$token_relist[] = $this->em_strong_relist["$em$strong"];
-				}
-				$token_relist[] = $em_re;
-				$token_relist[] = $strong_re;
-
-				// Construct master expression from list.
-				$token_re = '{(' . implode('|', $token_relist) . ')}';
-				$this->em_strong_prepared_relist["$em$strong"] = $token_re;
-			}
-		}
-	}
-
-	/**
-	 * Convert Markdown italics (emphasis) and bold (strong) to HTML
-	 * @param  string $text
-	 * @return string
-	 */
-	protected function doItalicsAndBold($text) {
-		if ($this->in_emphasis_processing) {
-			return $text; // avoid reentrency
-		}
-		$this->in_emphasis_processing = true;
-
-		$token_stack = array('');
-		$text_stack = array('');
-		$em = '';
-		$strong = '';
-		$tree_char_em = false;
-
-		while (1) {
-			// Get prepared regular expression for seraching emphasis tokens
-			// in current context.
-			$token_re = $this->em_strong_prepared_relist["$em$strong"];
-
-			// Each loop iteration search for the next emphasis token.
-			// Each token is then passed to handleSpanToken.
-			$parts = preg_split($token_re, $text, 2, PREG_SPLIT_DELIM_CAPTURE);
-			$text_stack[0] .= $parts[0];
-			$token =& $parts[1];
-			$text =& $parts[2];
-
-			if (empty($token)) {
-				// Reached end of text span: empty stack without emitting.
-				// any more emphasis.
-				while ($token_stack[0]) {
-					$text_stack[1] .= array_shift($token_stack);
-					$text_stack[0] .= array_shift($text_stack);
-				}
-				break;
-			}
-
-			$token_len = strlen($token);
-			if ($tree_char_em) {
-				// Reached closing marker while inside a three-char emphasis.
-				if ($token_len == 3) {
-					// Three-char closing marker, close em and strong.
-					array_shift($token_stack);
-					$span = array_shift($text_stack);
-					$span = $this->runSpanGamut($span);
-					$span = "$span";
-					$text_stack[0] .= $this->hashPart($span);
-					$em = '';
-					$strong = '';
-				} else {
-					// Other closing marker: close one em or strong and
-					// change current token state to match the other
-					$token_stack[0] = str_repeat($token[0], 3-$token_len);
-					$tag = $token_len == 2 ? "strong" : "em";
-					$span = $text_stack[0];
-					$span = $this->runSpanGamut($span);
-					$span = "<$tag>$span";
-					$text_stack[0] = $this->hashPart($span);
-					$$tag = ''; // $$tag stands for $em or $strong
-				}
-				$tree_char_em = false;
-			} else if ($token_len == 3) {
-				if ($em) {
-					// Reached closing marker for both em and strong.
-					// Closing strong marker:
-					for ($i = 0; $i < 2; ++$i) {
-						$shifted_token = array_shift($token_stack);
-						$tag = strlen($shifted_token) == 2 ? "strong" : "em";
-						$span = array_shift($text_stack);
-						$span = $this->runSpanGamut($span);
-						$span = "<$tag>$span";
-						$text_stack[0] .= $this->hashPart($span);
-						$$tag = ''; // $$tag stands for $em or $strong
-					}
-				} else {
-					// Reached opening three-char emphasis marker. Push on token
-					// stack; will be handled by the special condition above.
-					$em = $token[0];
-					$strong = "$em$em";
-					array_unshift($token_stack, $token);
-					array_unshift($text_stack, '');
-					$tree_char_em = true;
-				}
-			} else if ($token_len == 2) {
-				if ($strong) {
-					// Unwind any dangling emphasis marker:
-					if (strlen($token_stack[0]) == 1) {
-						$text_stack[1] .= array_shift($token_stack);
-						$text_stack[0] .= array_shift($text_stack);
-						$em = '';
-					}
-					// Closing strong marker:
-					array_shift($token_stack);
-					$span = array_shift($text_stack);
-					$span = $this->runSpanGamut($span);
-					$span = "$span";
-					$text_stack[0] .= $this->hashPart($span);
-					$strong = '';
-				} else {
-					array_unshift($token_stack, $token);
-					array_unshift($text_stack, '');
-					$strong = $token;
-				}
-			} else {
-				// Here $token_len == 1
-				if ($em) {
-					if (strlen($token_stack[0]) == 1) {
-						// Closing emphasis marker:
-						array_shift($token_stack);
-						$span = array_shift($text_stack);
-						$span = $this->runSpanGamut($span);
-						$span = "$span";
-						$text_stack[0] .= $this->hashPart($span);
-						$em = '';
-					} else {
-						$text_stack[0] .= $token;
-					}
-				} else {
-					array_unshift($token_stack, $token);
-					array_unshift($text_stack, '');
-					$em = $token;
-				}
-			}
-		}
-		$this->in_emphasis_processing = false;
-		return $text_stack[0];
-	}
-
-	/**
-	 * Parse Markdown blockquotes to HTML
-	 * @param  string $text
-	 * @return string
-	 */
-	protected function doBlockQuotes($text) {
-		$text = preg_replace_callback('/
-			  (								# Wrap whole match in $1
-				(?>
-				  ^[ ]*>[ ]?			# ">" at the start of a line
-					.+\n					# rest of the first line
-				  (.+\n)*					# subsequent consecutive lines
-				  \n*						# blanks
-				)+
-			  )
-			/xm',
-			array($this, '_doBlockQuotes_callback'), $text);
-
-		return $text;
-	}
-
-	/**
-	 * Blockquote parsing callback
-	 * @param  array $matches
-	 * @return string
-	 */
-	protected function _doBlockQuotes_callback($matches) {
-		$bq = $matches[1];
-		// trim one level of quoting - trim whitespace-only lines
-		$bq = preg_replace('/^[ ]*>[ ]?|^[ ]+$/m', '', $bq);
-		$bq = $this->runBlockGamut($bq); // recurse
-
-		$bq = preg_replace('/^/m', "  ", $bq);
-		// These leading spaces cause problem with 
     content,
-		// so we need to fix that:
-		$bq = preg_replace_callback('{(\s*
    .+?
    )}sx',
-			array($this, '_doBlockQuotes_callback2'), $bq);
-
-		return "\n" . $this->hashBlock("
    \n$bq\n
    ") . "\n\n";
-	}
-
-	/**
-	 * Blockquote parsing callback
-	 * @param  array $matches
-	 * @return string
-	 */
-	protected function _doBlockQuotes_callback2($matches) {
-		$pre = $matches[1];
-		$pre = preg_replace('/^  /m', '', $pre);
-		return $pre;
-	}
-
-	/**
-	 * Parse paragraphs
-	 *
-	 * @param  string $text String to process in paragraphs
-	 * @param  boolean $wrap_in_p Whether paragraphs should be wrapped in 
     tags
-	 * @return string
-	 */
-	protected function formParagraphs($text, $wrap_in_p = true) {
-		// Strip leading and trailing lines:
-		$text = preg_replace('/\A\n+|\n+\z/', '', $text);
-
-		$grafs = preg_split('/\n{2,}/', $text, -1, PREG_SPLIT_NO_EMPTY);
-
-		// Wrap 
     tags and unhashify HTML blocks
-		foreach ($grafs as $key => $value) {
-			if (!preg_match('/^B\x1A[0-9]+B$/', $value)) {
-				// Is a paragraph.
-				$value = $this->runSpanGamut($value);
-				if ($wrap_in_p) {
-					$value = preg_replace('/^([ ]*)/', "
    ", $value);
-					$value .= "
    ";
-				}
-				$grafs[$key] = $this->unhash($value);
-			} else {
-				// Is a block.
-				// Modify elements of @grafs in-place...
-				$graf = $value;
-				$block = $this->html_hashes[$graf];
-				$graf = $block;
-//				if (preg_match('{
-//					\A
-//					(							# $1 = 
     tag
-//					  
    ]*
-//					  \b
-//					  markdown\s*=\s*  ([\'"])	#	$2 = attr quote char
-//					  1
-//					  \2
-//					  [^>]*
-//					  >
-//					)
-//					(							# $3 = contents
-//					.*
-//					)
-//					(
    )					# $4 = closing tag
-//					\z
-//					}xs', $block, $matches))
-//				{
-//					list(, $div_open, , $div_content, $div_close) = $matches;
-//
-//					// We can't call Markdown(), because that resets the hash;
-//					// that initialization code should be pulled into its own sub, though.
-//					$div_content = $this->hashHTMLBlocks($div_content);
-//
-//					// Run document gamut methods on the content.
-//					foreach ($this->document_gamut as $method => $priority) {
-//						$div_content = $this->$method($div_content);
-//					}
-//
-//					$div_open = preg_replace(
-//						'{\smarkdown\s*=\s*([\'"]).+?\1}', '', $div_open);
-//
-//					$graf = $div_open . "\n" . $div_content . "\n" . $div_close;
-//				}
-				$grafs[$key] = $graf;
-			}
-		}
-
-		return implode("\n\n", $grafs);
-	}
-
-	/**
-	 * Encode text for a double-quoted HTML attribute. This function
-	 * is *not* suitable for attributes enclosed in single quotes.
-	 * @param  string $text
-	 * @return string
-	 */
-	protected function encodeAttribute($text) {
-		$text = $this->encodeAmpsAndAngles($text);
-		$text = str_replace('"', '"', $text);
-		return $text;
-	}
-
-	/**
-	 * Encode text for a double-quoted HTML attribute containing a URL,
-	 * applying the URL filter if set. Also generates the textual
-	 * representation for the URL (removing mailto: or tel:) storing it in $text.
-	 * This function is *not* suitable for attributes enclosed in single quotes.
-	 *
-	 * @param  string $url
-	 * @param  string $text Passed by reference
-	 * @return string        URL
-	 */
-	protected function encodeURLAttribute($url, &$text = null) {
-		if (is_callable($this->url_filter_func)) {
-			$url = call_user_func($this->url_filter_func, $url);
-		}
-
-		if (preg_match('{^mailto:}i', $url)) {
-			$url = $this->encodeEntityObfuscatedAttribute($url, $text, 7);
-		} else if (preg_match('{^tel:}i', $url)) {
-			$url = $this->encodeAttribute($url);
-			$text = substr($url, 4);
-		} else {
-			$url = $this->encodeAttribute($url);
-			$text = $url;
-		}
-
-		return $url;
-	}
-
-	/**
-	 * Smart processing for ampersands and angle brackets that need to
-	 * be encoded. Valid character entities are left alone unless the
-	 * no-entities mode is set.
-	 * @param  string $text
-	 * @return string
-	 */
-	protected function encodeAmpsAndAngles($text) {
-		if ($this->no_entities) {
-			$text = str_replace('&', '&', $text);
-		} else {
-			// Ampersand-encoding based entirely on Nat Irons's Amputator
-			// MT plugin: 
-			$text = preg_replace('/&(?!#?[xX]?(?:[0-9a-fA-F]+|\w+);)/',
-								'&', $text);
-		}
-		// Encode remaining <'s
-		$text = str_replace('<', '<', $text);
-
-		return $text;
-	}
-
-	/**
-	 * Parse Markdown automatic links to anchor HTML tags
-	 * @param  string $text
-	 * @return string
-	 */
-	protected function doAutoLinks($text) {
-		$text = preg_replace_callback('{<((https?|ftp|dict|tel):[^\'">\s]+)>}i',
-			array($this, '_doAutoLinks_url_callback'), $text);
-
-		// Email addresses: 
-		$text = preg_replace_callback('{
-			<
-			(?:mailto:)?
-			(
-				(?:
-					[-!#$%&\'*+/=?^_`.{|}~\w\x80-\xFF]+
-				|
-					".*?"
-				)
-				\@
-				(?:
-					[-a-z0-9\x80-\xFF]+(\.[-a-z0-9\x80-\xFF]+)*\.[a-z]+
-				|
-					\[[\d.a-fA-F:]+\]	# IPv4 & IPv6
-				)
-			)
-			>
-			}xi',
-			array($this, '_doAutoLinks_email_callback'), $text);
-
-		return $text;
-	}
-
-	/**
-	 * Parse URL callback
-	 * @param  array $matches
-	 * @return string
-	 */
-	protected function _doAutoLinks_url_callback($matches) {
-		$url = $this->encodeURLAttribute($matches[1], $text);
-		$link = "$text";
-		return $this->hashPart($link);
-	}
-
-	/**
-	 * Parse email address callback
-	 * @param  array $matches
-	 * @return string
-	 */
-	protected function _doAutoLinks_email_callback($matches) {
-		$addr = $matches[1];
-		$url = $this->encodeURLAttribute("mailto:$addr", $text);
-		$link = "$text";
-		return $this->hashPart($link);
-	}
-
-	/**
-	 * Input: some text to obfuscate, e.g. "mailto:foo@example.com"
-	 *
-	 * Output: the same text but with most characters encoded as either a
-	 *         decimal or hex entity, in the hopes of foiling most address
-	 *         harvesting spam bots. E.g.:
-	 *
-	 *        mailto:foo
-	 *        @example.co
-	 *        m
-	 *
-	 * Note: the additional output $tail is assigned the same value as the
-	 * ouput, minus the number of characters specified by $head_length.
-	 *
-	 * Based by a filter by Matthew Wickline, posted to BBEdit-Talk.
-	 * With some optimizations by Milian Wolff. Forced encoding of HTML
-	 * attribute special characters by Allan Odgaard.
-	 *
-	 * @param  string  $text
-	 * @param  string  $tail Passed by reference
-	 * @param  integer $head_length
-	 * @return string
-	 */
-	protected function encodeEntityObfuscatedAttribute($text, &$tail = null, $head_length = 0) {
-		if ($text == "") {
-			return $tail = "";
-		}
-
-		$chars = preg_split('/(? $char) {
-			$ord = ord($char);
-			// Ignore non-ascii chars.
-			if ($ord < 128) {
-				$r = ($seed * (1 + $key)) % 100; // Pseudo-random function.
-				// roughly 10% raw, 45% hex, 45% dec
-				// '@' *must* be encoded. I insist.
-				// '"' and '>' have to be encoded inside the attribute
-				if ($r > 90 && strpos('@"&>', $char) === false) {
-					/* do nothing */
-				} else if ($r < 45) {
-					$chars[$key] = '&#x'.dechex($ord).';';
-				} else {
-					$chars[$key] = '&#'.$ord.';';
-				}
-			}
-		}
-
-		$text = implode('', $chars);
-		$tail = $head_length ? implode('', array_slice($chars, $head_length)) : $text;
-
-		return $text;
-	}
-
-	/**
-	 * Take the string $str and parse it into tokens, hashing embeded HTML,
-	 * escaped characters and handling code spans.
-	 * @param  string $str
-	 * @return string
-	 */
-	protected function parseSpan($str) {
-		$output = '';
-
-		$span_re = '{
-				(
-					\\\\'.$this->escape_chars_re.'
-				|
-					(?no_markup ? '' : '
-				|
-							# comment
-				|
-					<\?.*?\?> | <%.*?%>		# processing instruction
-				|
-					<[!$]?[-a-zA-Z0-9:_]+	# regular tags
-					(?>
-						\s
-						(?>[^"\'>]+|"[^"]*"|\'[^\']*\')*
-					)?
-					>
-				|
-					<[-a-zA-Z0-9:_]+\s*/> # xml-style empty tag
-				|
-					 # closing tag
-			').'
-				)
-				}xs';
-
-		while (1) {
-			// Each loop iteration seach for either the next tag, the next
-			// openning code span marker, or the next escaped character.
-			// Each token is then passed to handleSpanToken.
-			$parts = preg_split($span_re, $str, 2, PREG_SPLIT_DELIM_CAPTURE);
-
-			// Create token from text preceding tag.
-			if ($parts[0] != "") {
-				$output .= $parts[0];
-			}
-
-			// Check if we reach the end.
-			if (isset($parts[1])) {
-				$output .= $this->handleSpanToken($parts[1], $parts[2]);
-				$str = $parts[2];
-			} else {
-				break;
-			}
-		}
-
-		return $output;
-	}
-
-	/**
-	 * Handle $token provided by parseSpan by determining its nature and
-	 * returning the corresponding value that should replace it.
-	 * @param  string $token
-	 * @param  string $str Passed by reference
-	 * @return string
-	 */
-	protected function handleSpanToken($token, &$str) {
-		switch ($token[0]) {
-			case "\\":
-				return $this->hashPart("&#". ord($token[1]). ";");
-			case "`":
-				// Search for end marker in remaining text.
-				if (preg_match('/^(.*?[^`])'.preg_quote($token).'(?!`)(.*)$/sm',
-					$str, $matches))
-				{
-					$str = $matches[2];
-					$codespan = $this->makeCodeSpan($matches[1]);
-					return $this->hashPart($codespan);
-				}
-				return $token; // Return as text since no ending marker found.
-			default:
-				return $this->hashPart($token);
-		}
-	}
-
-	/**
-	 * Remove one level of line-leading tabs or spaces
-	 * @param  string $text
-	 * @return string
-	 */
-	protected function outdent($text) {
-		return preg_replace('/^(\t|[ ]{1,' . $this->tab_width . '})/m', '', $text);
-	}
-
-
-	/**
-	 * String length function for detab. `_initDetab` will create a function to
-	 * handle UTF-8 if the default function does not exist.
-	 * can be a string or function
-	 */
-	protected $utf8_strlen = 'mb_strlen';
-
-	/**
-	 * Replace tabs with the appropriate amount of spaces.
-	 *
-	 * For each line we separate the line in blocks delemited by tab characters.
-	 * Then we reconstruct every line by adding the  appropriate number of space
-	 * between each blocks.
-	 *
-	 * @param  string $text
-	 * @return string
-	 */
-	protected function detab($text) {
-		$text = preg_replace_callback('/^.*\t.*$/m',
-			array($this, '_detab_callback'), $text);
-
-		return $text;
-	}
-
-	/**
-	 * Replace tabs callback
-	 * @param  string $matches
-	 * @return string
-	 */
-	protected function _detab_callback($matches) {
-		$line = $matches[0];
-		$strlen = $this->utf8_strlen; // strlen function for UTF-8.
-
-		// Split in blocks.
-		$blocks = explode("\t", $line);
-		// Add each blocks to the line.
-		$line = $blocks[0];
-		unset($blocks[0]); // Do not add first block twice.
-		foreach ($blocks as $block) {
-			// Calculate amount of space, insert spaces, insert block.
-			$amount = $this->tab_width -
-				$strlen($line, 'UTF-8') % $this->tab_width;
-			$line .= str_repeat(" ", $amount) . $block;
-		}
-		return $line;
-	}
-
-	/**
-	 * Check for the availability of the function in the `utf8_strlen` property
-	 * (initially `mb_strlen`). If the function is not available, create a
-	 * function that will loosely count the number of UTF-8 characters with a
-	 * regular expression.
-	 * @return void
-	 */
-	protected function _initDetab() {
-
-		if (function_exists($this->utf8_strlen)) {
-			return;
-		}
-
-		//$this->utf8_strlen = fn($text) => preg_match_all('/[\x00-\xBF]|[\xC0-\xFF][\x80-\xBF]*/', $text, $m);
-	}
-
-	/**
-	 * Swap back in all the tags hashed by _HashHTMLBlocks.
-	 * @param  string $text
-	 * @return string
-	 */
-	protected function unhash($text) {
-		return preg_replace_callback('/(.)\x1A[0-9]+\1/',
-			array($this, '_unhash_callback'), $text);
-	}
-
-	/**
-	 * Unhashing callback
-	 * @param  array $matches
-	 * @return string
-	 */
-	protected function _unhash_callback($matches) {
-		return $this->html_hashes[$matches[0]];
-	}
-}
diff --git a/lib/michelf/Michelf/MarkdownExtra.inc.php b/lib/michelf/Michelf/MarkdownExtra.inc.php
deleted file mode 100644
index d09bd7a480..0000000000
--- a/lib/michelf/Michelf/MarkdownExtra.inc.php
+++ /dev/null
@@ -1,11 +0,0 @@
-
- * @copyright 2004-2019 Michel Fortin 
- * @copyright (Original Markdown) 2004-2006 John Gruber 
- */
-
-namespace Michelf;
-
-/**
- * Markdown Extra Parser Class
- */
-class MarkdownExtra extends \Michelf\Markdown {
-	/**
-	 * Configuration variables
-	 */
-	/**
-	 * Prefix for footnote ids.
-	 */
-	public $fn_id_prefix = "";
-
-	/**
-	 * Optional title attribute for footnote links.
-	 */
-	public $fn_link_title = "";
-
-	/**
-	 * Optional class attribute for footnote links and backlinks.
-	 */
-	public $fn_link_class     = "footnote-ref";
-	public $fn_backlink_class = "footnote-backref";
-
-	/**
-	 * Content to be displayed within footnote backlinks. The default is '↩';
-	 * the U+FE0E on the end is a Unicode variant selector used to prevent iOS
-	 * from displaying the arrow character as an emoji.
-	 * Optionally use '^^' and '%%' to refer to the footnote number and
-	 * reference number respectively. {@see parseFootnotePlaceholders()}
-	 */
-	public $fn_backlink_html = '↩︎';
-
-	/**
-	 * Optional title and aria-label attributes for footnote backlinks for
-	 * added accessibility (to ensure backlink uniqueness).
-	 * Use '^^' and '%%' to refer to the footnote number and reference number
-	 * respectively. {@see parseFootnotePlaceholders()}
-	 */
-	public $fn_backlink_title = "";
-	public $fn_backlink_label = "";
-
-	/**
-	 * Class name for table cell alignment (%% replaced left/center/right)
-	 * For instance: 'go-%%' becomes 'go-left' or 'go-right' or 'go-center'
-	 * If empty, the align attribute is used instead of a class name.
-	 */
-	public $table_align_class_tmpl = '';
-
-	/**
-	 * Optional class prefix for fenced code block.
-	 */
-	public $code_class_prefix = "";
-
-	/**
-	 * Class attribute for code blocks goes on the `code` tag;
-	 * setting this to true will put attributes on the `pre` tag instead.
-	 */
-	public $code_attr_on_pre = false;
-
-	/**
-	 * Predefined abbreviations.
-	 */
-	public $predef_abbr = array();
-
-	/**
-	 * Only convert atx-style headers if there's a space between the header and #
-	 */
-	public $hashtag_protection = false;
-
-	/**
-	 * Determines whether footnotes should be appended to the end of the document.
-	 * If true, footnote html can be retrieved from $this->footnotes_assembled.
-	 */
-	public $omit_footnotes = false;
-
-
-	/**
-	 * After parsing, the HTML for the list of footnotes appears here.
-	 * This is available only if $omit_footnotes == true.
-	 *
-	 * Note: when placing the content of `footnotes_assembled` on the page,
-	 * consider adding the attribute `role="doc-endnotes"` to the `div` or
-	 * `section` that will enclose the list of footnotes so they are
-	 * reachable to accessibility tools the same way they would be with the
-	 * default HTML output.
-	 */
-	public $footnotes_assembled = null;
-
-	/**
-	 * Parser implementation
-	 */
-
-	/**
-	 * Constructor function. Initialize the parser object.
-	 * @return void
-	 */
-	public function __construct() {
-		// Add extra escapable characters before parent constructor
-		// initialize the table.
-		$this->escape_chars .= ':|';
-
-		// Insert extra document, block, and span transformations.
-		// Parent constructor will do the sorting.
-		$this->document_gamut += array(
-			"doFencedCodeBlocks" => 5,
-			"stripFootnotes"     => 15,
-			"stripAbbreviations" => 25,
-			"appendFootnotes"    => 50,
-		);
-		$this->block_gamut += array(
-			"doFencedCodeBlocks" => 5,
-			"doTables"           => 15,
-			"doDefLists"         => 45,
-		);
-		$this->span_gamut += array(
-			"doFootnotes"        => 5,
-			"doAbbreviations"    => 70,
-		);
-
-		$this->enhanced_ordered_list = true;
-		parent::__construct();
-	}
-
-
-	/**
-	 * Extra variables used during extra transformations.
-	 */
-	protected $footnotes = array();
-	protected $footnotes_ordered = array();
-	protected $footnotes_ref_count = array();
-	protected $footnotes_numbers = array();
-	protected $abbr_desciptions = array();
-	protected $abbr_word_re = '';
-
-	/**
-	 * Give the current footnote number.
-	 */
-	protected $footnote_counter = 1;
-
-    /**
-	 * Ref attribute for links
-	 */
-	protected $ref_attr = array();
-
-	/**
-	 * Setting up Extra-specific variables.
-	 */
-	protected function setup() {
-		parent::setup();
-
-		$this->footnotes = array();
-		$this->footnotes_ordered = array();
-		$this->footnotes_ref_count = array();
-		$this->footnotes_numbers = array();
-		$this->abbr_desciptions = array();
-		$this->abbr_word_re = '';
-		$this->footnote_counter = 1;
-		$this->footnotes_assembled = null;
-
-		foreach ($this->predef_abbr as $abbr_word => $abbr_desc) {
-			if ($this->abbr_word_re)
-				$this->abbr_word_re .= '|';
-			$this->abbr_word_re .= preg_quote($abbr_word);
-			$this->abbr_desciptions[$abbr_word] = trim($abbr_desc);
-		}
-	}
-
-	/**
-	 * Clearing Extra-specific variables.
-	 */
-	protected function teardown() {
-		$this->footnotes = array();
-		$this->footnotes_ordered = array();
-		$this->footnotes_ref_count = array();
-		$this->footnotes_numbers = array();
-		$this->abbr_desciptions = array();
-		$this->abbr_word_re = '';
-
-		if ( ! $this->omit_footnotes )
-			$this->footnotes_assembled = null;
-
-		parent::teardown();
-	}
-
-
-	/**
-	 * Extra attribute parser
-	 */
-	/**
-	 * Expression to use to catch attributes (includes the braces)
-	 */
-	protected $id_class_attr_catch_re = '\{((?>[ ]*[#.a-z][-_:a-zA-Z0-9=]+){1,})[ ]*\}';
-
-	/**
-	 * Expression to use when parsing in a context when no capture is desired
-	 */
-	protected $id_class_attr_nocatch_re = '\{(?>[ ]*[#.a-z][-_:a-zA-Z0-9=]+){1,}[ ]*\}';
-
-	/**
-	 * Parse attributes caught by the $this->id_class_attr_catch_re expression
-	 * and return the HTML-formatted list of attributes.
-	 *
-	 * Currently supported attributes are .class and #id.
-	 *
-	 * In addition, this method also supports supplying a default Id value,
-	 * which will be used to populate the id attribute in case it was not
-	 * overridden.
-	 * @param  string $tag_name
-	 * @param  string $attr
-	 * @param  mixed  $defaultIdValue
-	 * @param  array  $classes
-	 * @return string
-	 */
-	protected function doExtraAttributes($tag_name, $attr, $defaultIdValue = null, $classes = array()) {
-		if (empty($attr) && !$defaultIdValue && empty($classes)) {
-			return "";
-		}
-
-		// Split on components
-		preg_match_all('/[#.a-z][-_:a-zA-Z0-9=]+/', $attr, $matches);
-		$elements = $matches[0];
-
-		// Handle classes and IDs (only first ID taken into account)
-		$attributes = array();
-		$id = false;
-		foreach ($elements as $element) {
-			if ($element[0] === '.') {
-				$classes[] = substr($element, 1);
-			} else if ($element[0] === '#') {
-				if ($id === false) $id = substr($element, 1);
-			} else if (strpos($element, '=') > 0) {
-				$parts = explode('=', $element, 2);
-				$attributes[] = $parts[0] . '="' . $parts[1] . '"';
-			}
-		}
-
-		if ($id === false || $id === '') {
-			$id = $defaultIdValue;
-		}
-
-		// Compose attributes as string
-		$attr_str = "";
-		if (!empty($id)) {
-			$attr_str .= ' id="'.$this->encodeAttribute($id) .'"';
-		}
-		if (!empty($classes)) {
-			$attr_str .= ' class="'. implode(" ", $classes) . '"';
-		}
-		if (!$this->no_markup && !empty($attributes)) {
-			$attr_str .= ' '.implode(" ", $attributes);
-		}
-		return $attr_str;
-	}
-
-	/**
-	 * Strips link definitions from text, stores the URLs and titles in
-	 * hash references.
-	 * @param  string $text
-	 * @return string
-	 */
-	protected function stripLinkDefinitions($text) {
-		$less_than_tab = $this->tab_width - 1;
-
-		// Link defs are in the form: ^[id]: url "optional title"
-		$text = preg_replace_callback('{
-							^[ ]{0,'.$less_than_tab.'}\[(.+)\][ ]?:	# id = $1
-							  [ ]*
-							  \n?				# maybe *one* newline
-							  [ ]*
-							(?:
-							  <(.+?)>			# url = $2
-							|
-							  (\S+?)			# url = $3
-							)
-							  [ ]*
-							  \n?				# maybe one newline
-							  [ ]*
-							(?:
-								(?<=\s)			# lookbehind for whitespace
-								["(]
-								(.*?)			# title = $4
-								[")]
-								[ ]*
-							)?	# title is optional
-					(?:[ ]* '.$this->id_class_attr_catch_re.' )?  # $5 = extra id & class attr
-							(?:\n+|\Z)
-			}xm',
-			array($this, '_stripLinkDefinitions_callback'),
-			$text);
-		return $text;
-	}
-
-	/**
-	 * Strip link definition callback
-	 * @param  array $matches
-	 * @return string
-	 */
-	protected function _stripLinkDefinitions_callback($matches) {
-		$link_id = strtolower($matches[1]);
-		$url = $matches[2] == '' ? $matches[3] : $matches[2];
-		$this->urls[$link_id] = $url;
-		$this->titles[$link_id] =& $matches[4];
-		$this->ref_attr[$link_id] = $this->doExtraAttributes("", $dummy =& $matches[5]);
-		return ''; // String that will replace the block
-	}
-
-
-	/**
-	 * HTML block parser
-	 */
-	/**
-	 * Tags that are always treated as block tags
-	 */
-	protected $block_tags_re = 'p|div|h[1-6]|blockquote|pre|table|dl|ol|ul|address|form|fieldset|iframe|hr|legend|article|section|nav|aside|hgroup|header|footer|figcaption|figure|details|summary';
-
-	/**
-	 * Tags treated as block tags only if the opening tag is alone on its line
-	 */
-	protected $context_block_tags_re = 'script|noscript|style|ins|del|iframe|object|source|track|param|math|svg|canvas|audio|video';
-
-	/**
-	 * Tags where markdown="1" default to span mode:
-	 */
-	protected $contain_span_tags_re = 'p|h[1-6]|li|dd|dt|td|th|legend|address';
-
-	/**
-	 * Tags which must not have their contents modified, no matter where
-	 * they appear
-	 */
-	protected $clean_tags_re = 'script|style|math|svg';
-
-	/**
-	 * Tags that do not need to be closed.
-	 */
-	protected $auto_close_tags_re = 'hr|img|param|source|track';
-
-	/**
-	 * Hashify HTML Blocks and "clean tags".
-	 *
-	 * We only want to do this for block-level HTML tags, such as headers,
-	 * lists, and tables. That's because we still want to wrap 
    s around
-	 * "paragraphs" that are wrapped in non-block-level tags, such as anchors,
-	 * phrase emphasis, and spans. The list of tags we're looking for is
-	 * hard-coded.
-	 *
-	 * This works by calling _HashHTMLBlocks_InMarkdown, which then calls
-	 * _HashHTMLBlocks_InHTML when it encounter block tags. When the markdown="1"
-	 * attribute is found within a tag, _HashHTMLBlocks_InHTML calls back
-	 *  _HashHTMLBlocks_InMarkdown to handle the Markdown syntax within the tag.
-	 * These two functions are calling each other. It's recursive!
-	 * @param  string $text
-	 * @return string
-	 */
-	protected function hashHTMLBlocks($text) {
-		if ($this->no_markup) {
-			return $text;
-		}
-
-		// Call the HTML-in-Markdown hasher.
-		list($text, ) = $this->_hashHTMLBlocks_inMarkdown($text);
-
-		return $text;
-	}
-
-	/**
-	 * Parse markdown text, calling _HashHTMLBlocks_InHTML for block tags.
-	 *
-	 * *   $indent is the number of space to be ignored when checking for code
-	 *     blocks. This is important because if we don't take the indent into
-	 *     account, something like this (which looks right) won't work as expected:
-	 *
-	 *     
    
-	 *         
    
-	 *         Hello World.  <-- Is this a Markdown code block or text?
-	 *         
      <-- Is this a Markdown code block or a real tag?
-	 *     
    
-	 *
-	 *     If you don't like this, just don't indent the tag on which
-	 *     you apply the markdown="1" attribute.
-	 *
-	 * *   If $enclosing_tag_re is not empty, stops at the first unmatched closing
-	 *     tag with that name. Nested tags supported.
-	 *
-	 * *   If $span is true, text inside must treated as span. So any double
-	 *     newline will be replaced by a single newline so that it does not create
-	 *     paragraphs.
-	 *
-	 * Returns an array of that form: ( processed text , remaining text )
-	 *
-	 * @param  string  $text
-	 * @param  integer $indent
-	 * @param  string  $enclosing_tag_re
-	 * @param  boolean $span
-	 * @return array
-	 */
-	protected function _hashHTMLBlocks_inMarkdown($text, $indent = 0,
-										$enclosing_tag_re = '', $span = false)
-	{
-
-		if ($text === '') return array('', '');
-
-		// Regex to check for the presense of newlines around a block tag.
-		$newline_before_re = '/(?:^\n?|\n\n)*$/';
-		$newline_after_re =
-			'{
-				^						# Start of text following the tag.
-				(?>[ ]*)?		# Optional comment.
-				[ ]*\n					# Must be followed by newline.
-			}xs';
-
-		// Regex to match any tag.
-		$block_tag_re =
-			'{
-				(					# $2: Capture whole tag.
-									# Tag name.
-							' . $this->block_tags_re . '			|
-							' . $this->context_block_tags_re . '	|
-							' . $this->clean_tags_re . '        	|
-							(?!\s)'.$enclosing_tag_re . '
-						)
-						(?:
-							(?=[\s"\'/a-zA-Z0-9])	# Allowed characters after tag name.
-							(?>
-								".*?"		|	# Double quotes (can contain `>`)
-								\'.*?\'   	|	# Single quotes (can contain `>`)
-								.+?				# Anything but quotes and `>`.
-							)*?
-						)?
-					>					# End of tag.
-				|
-						# HTML Comment
-				|
-					<\?.*?\?> | <%.*?%>	# Processing instruction
-				|
-						# CData Block
-				' . ( !$span ? ' # If not in span.
-				|
-					# Indented code block
-					(?: ^[ ]*\n | ^ | \n[ ]*\n )
-					[ ]{' . ($indent + 4) . '}[^\n]* \n
-					(?>
-						(?: [ ]{' . ($indent + 4) . '}[^\n]* | [ ]* ) \n
-					)*
-				|
-					# Fenced code block marker
-					(?<= ^ | \n )
-					[ ]{0,' . ($indent + 3) . '}(?:~{3,}|`{3,})
-					[ ]*
-					(?: \.?[-_:a-zA-Z0-9]+ )? # standalone class name
-					[ ]*
-					(?: ' . $this->id_class_attr_nocatch_re . ' )? # extra attributes
-					[ ]*
-					(?= \n )
-				' : '' ) . ' # End (if not is span).
-				|
-					# Code span marker
-					# Note, this regex needs to go after backtick fenced
-					# code blocks but it should also be kept outside of the
-					# "if not in span" condition adding backticks to the parser
-					`+
-				)
-			}xs';
-
-
-		$depth = 0;		// Current depth inside the tag tree.
-		$parsed = "";	// Parsed text that will be returned.
-
-		// Loop through every tag until we find the closing tag of the parent
-		// or loop until reaching the end of text if no parent tag specified.
-		do {
-			// Split the text using the first $tag_match pattern found.
-			// Text before  pattern will be first in the array, text after
-			// pattern will be at the end, and between will be any catches made
-			// by the pattern.
-			$parts = preg_split($block_tag_re, $text, 2,
-								PREG_SPLIT_DELIM_CAPTURE);
-
-			// If in Markdown span mode, add a empty-string span-level hash
-			// after each newline to prevent triggering any block element.
-			if ($span) {
-				$void = $this->hashPart("", ':');
-				$newline = "\n$void";
-				$parts[0] = $void . str_replace("\n", $newline, $parts[0]) . $void;
-			}
-
-			$parsed .= $parts[0]; // Text before current tag.
-
-			// If end of $text has been reached. Stop loop.
-			if (count($parts) < 3) {
-				$text = "";
-				break;
-			}
-
-			$tag  = $parts[1]; // Tag to handle.
-			$text = $parts[2]; // Remaining text after current tag.
-
-			// Check for: Fenced code block marker.
-			// Note: need to recheck the whole tag to disambiguate backtick
-			// fences from code spans
-			if (preg_match('{^\n?([ ]{0,' . ($indent + 3) . '})(~{3,}|`{3,})[ ]*(?:\.?[-_:a-zA-Z0-9]+)?[ ]*(?:' . $this->id_class_attr_nocatch_re . ')?[ ]*\n?$}', $tag, $capture)) {
-				// Fenced code block marker: find matching end marker.
-				$fence_indent = strlen($capture[1]); // use captured indent in re
-				$fence_re = $capture[2]; // use captured fence in re
-				if (preg_match('{^(?>.*\n)*?[ ]{' . ($fence_indent) . '}' . $fence_re . '[ ]*(?:\n|$)}', $text,
-					$matches))
-				{
-					// End marker found: pass text unchanged until marker.
-					$parsed .= $tag . $matches[0];
-					$text = substr($text, strlen($matches[0]));
-				}
-				else {
-					// No end marker: just skip it.
-					$parsed .= $tag;
-				}
-			}
-			// Check for: Indented code block.
-			else if ($tag[0] === "\n" || $tag[0] === " ") {
-				// Indented code block: pass it unchanged, will be handled
-				// later.
-				$parsed .= $tag;
-			}
-			// Check for: Code span marker
-			// Note: need to check this after backtick fenced code blocks
-			else if ($tag[0] === "`") {
-				// Find corresponding end marker.
-				$tag_re = preg_quote($tag);
-				if (preg_match('{^(?>.+?|\n(?!\n))*?(?block_tags_re . ')\b}', $tag) ||
-				(	preg_match('{^<(?:' . $this->context_block_tags_re . ')\b}', $tag) &&
-					preg_match($newline_before_re, $parsed) &&
-					preg_match($newline_after_re, $text)	)
-				)
-			{
-				// Need to parse tag and following text using the HTML parser.
-				list($block_text, $text) =
-					$this->_hashHTMLBlocks_inHTML($tag . $text, "hashBlock", true);
-
-				// Make sure it stays outside of any paragraph by adding newlines.
-				$parsed .= "\n\n$block_text\n\n";
-			}
-			// Check for: Clean tag (like script, math)
-			//            HTML Comments, processing instructions.
-			else if (preg_match('{^<(?:' . $this->clean_tags_re . ')\b}', $tag) ||
-				$tag[1] === '!' || $tag[1] === '?')
-			{
-				// Need to parse tag and following text using the HTML parser.
-				// (don't check for markdown attribute)
-				list($block_text, $text) =
-					$this->_hashHTMLBlocks_inHTML($tag . $text, "hashClean", false);
-
-				$parsed .= $block_text;
-			}
-			// Check for: Tag with same name as enclosing tag.
-			else if ($enclosing_tag_re !== '' &&
-				// Same name as enclosing tag.
-				preg_match('{^= 0);
-
-		return array($parsed, $text);
-	}
-
-	/**
-	 * Parse HTML, calling _HashHTMLBlocks_InMarkdown for block tags.
-	 *
-	 * *   Calls $hash_method to convert any blocks.
-	 * *   Stops when the first opening tag closes.
-	 * *   $md_attr indicate if the use of the `markdown="1"` attribute is allowed.
-	 *     (it is not inside clean tags)
-	 *
-	 * Returns an array of that form: ( processed text , remaining text )
-	 * @param  string $text
-	 * @param  string $hash_method
-	 * @param  bool $md_attr Handle `markdown="1"` attribute
-	 * @return array
-	 */
-	protected function _hashHTMLBlocks_inHTML($text, $hash_method, $md_attr) {
-		if ($text === '') return array('', '');
-
-		// Regex to match `markdown` attribute inside of a tag.
-		$markdown_attr_re = '
-			{
-				\s*			# Eat whitespace before the `markdown` attribute
-				markdown
-				\s*=\s*
-				(?>
-					(["\'])		# $1: quote delimiter
-					(.*?)		# $2: attribute value
-					\1			# matching delimiter
-				|
-					([^\s>]*)	# $3: unquoted attribute value
-				)
-				()				# $4: make $3 always defined (avoid warnings)
-			}xs';
-
-		// Regex to match any tag.
-		$tag_re = '{
-				(					# $2: Capture whole tag.
-					
-								".*?"		|	# Double quotes (can contain `>`)
-								\'.*?\'   	|	# Single quotes (can contain `>`)
-								.+?				# Anything but quotes and `>`.
-							)*?
-						)?
-					>					# End of tag.
-				|
-						# HTML Comment
-				|
-					<\?.*?\?> | <%.*?%>	# Processing instruction
-				|
-						# CData Block
-				)
-			}xs';
-
-		$original_text = $text;		// Save original text in case of faliure.
-
-		$depth		= 0;	// Current depth inside the tag tree.
-		$block_text	= "";	// Temporary text holder for current text.
-		$parsed		= "";	// Parsed text that will be returned.
-		$base_tag_name_re = '';
-
-		// Get the name of the starting tag.
-		// (This pattern makes $base_tag_name_re safe without quoting.)
-		if (preg_match('/^<([\w:$]*)\b/', $text, $matches))
-			$base_tag_name_re = $matches[1];
-
-		// Loop through every tag until we find the corresponding closing tag.
-		do {
-			// Split the text using the first $tag_match pattern found.
-			// Text before  pattern will be first in the array, text after
-			// pattern will be at the end, and between will be any catches made
-			// by the pattern.
-			$parts = preg_split($tag_re, $text, 2, PREG_SPLIT_DELIM_CAPTURE);
-
-			if (count($parts) < 3) {
-				// End of $text reached with unbalenced tag(s).
-				// In that case, we return original text unchanged and pass the
-				// first character as filtered to prevent an infinite loop in the
-				// parent function.
-				return array($original_text[0], substr($original_text, 1));
-			}
-
-			$block_text .= $parts[0]; // Text before current tag.
-			$tag         = $parts[1]; // Tag to handle.
-			$text        = $parts[2]; // Remaining text after current tag.
-
-			// Check for: Auto-close tag (like 
    )
-			//			 Comments and Processing Instructions.
-			if (preg_match('{^auto_close_tags_re . ')\b}', $tag) ||
-				$tag[1] === '!' || $tag[1] === '?')
-			{
-				// Just add the tag to the block as if it was text.
-				$block_text .= $tag;
-			}
-			else {
-				// Increase/decrease nested tag count. Only do so if
-				// the tag's name match base tag's.
-				if (preg_match('{^contain_span_tags_re . ')\b}', $tag));
-
-					// Calculate indent before tag.
-					if (preg_match('/(?:^|\n)( *?)(?! ).*?$/', $block_text, $matches)) {
-						$strlen = $this->utf8_strlen;
-						$indent = $strlen($matches[1], 'UTF-8');
-					} else {
-						$indent = 0;
-					}
-
-					// End preceding block with this tag.
-					$block_text .= $tag;
-					$parsed .= $this->$hash_method($block_text);
-
-					// Get enclosing tag name for the ParseMarkdown function.
-					// (This pattern makes $tag_name_re safe without quoting.)
-					preg_match('/^<([\w:$]*)\b/', $tag, $matches);
-					$tag_name_re = $matches[1];
-
-					// Parse the content using the HTML-in-Markdown parser.
-					list ($block_text, $text)
-						= $this->_hashHTMLBlocks_inMarkdown($text, $indent,
-							$tag_name_re, $span_mode);
-
-					// Outdent markdown text.
-					if ($indent > 0) {
-						$block_text = preg_replace("/^[ ]{1,$indent}/m", "",
-													$block_text);
-					}
-
-					// Append tag content to parsed text.
-					if (!$span_mode) {
-						$parsed .= "\n\n$block_text\n\n";
-					} else {
-						$parsed .= (string) $block_text;
-					}
-
-					// Start over with a new block.
-					$block_text = "";
-				}
-				else $block_text .= $tag;
-			}
-
-		} while ($depth > 0);
-
-		// Hash last block text that wasn't processed inside the loop.
-		$parsed .= $this->$hash_method($block_text);
-
-		return array($parsed, $text);
-	}
-
-	/**
-	 * Called whenever a tag must be hashed when a function inserts a "clean" tag
-	 * in $text, it passes through this function and is automaticaly escaped,
-	 * blocking invalid nested overlap.
-	 * @param  string $text
-	 * @return string
-	 */
-	protected function hashClean($text) {
-		return $this->hashPart($text, 'C');
-	}
-
-	/**
-	 * Turn Markdown link shortcuts into XHTML  tags.
-	 * @param  string $text
-	 * @return string
-	 */
-	protected function doAnchors($text) {
-		if ($this->in_anchor) {
-			return $text;
-		}
-		$this->in_anchor = true;
-
-		// First, handle reference-style links: [link text] [id]
-		$text = preg_replace_callback('{
-			(					# wrap whole match in $1
-			  \[
-				(' . $this->nested_brackets_re . ')	# link text = $2
-			  \]
-
-			  [ ]?				# one optional space
-			  (?:\n[ ]*)?		# one optional newline followed by spaces
-
-			  \[
-				(.*?)		# id = $3
-			  \]
-			)
-			}xs',
-			array($this, '_doAnchors_reference_callback'), $text);
-
-		// Next, inline-style links: [link text](url "optional title")
-		$text = preg_replace_callback('{
-			(				# wrap whole match in $1
-			  \[
-				(' . $this->nested_brackets_re . ')	# link text = $2
-			  \]
-			  \(			# literal paren
-				[ \n]*
-				(?:
-					<(.+?)>	# href = $3
-				|
-					(' . $this->nested_url_parenthesis_re . ')	# href = $4
-				)
-				[ \n]*
-				(			# $5
-				  ([\'"])	# quote char = $6
-				  (.*?)		# Title = $7
-				  \6		# matching quote
-				  [ \n]*	# ignore any spaces/tabs between closing quote and )
-				)?			# title is optional
-			  \)
-			  (?:[ ]? ' . $this->id_class_attr_catch_re . ' )?	 # $8 = id/class attributes
-			)
-			}xs',
-			array($this, '_doAnchors_inline_callback'), $text);
-
-		// Last, handle reference-style shortcuts: [link text]
-		// These must come last in case you've also got [link text][1]
-		// or [link text](/foo)
-		$text = preg_replace_callback('{
-			(					# wrap whole match in $1
-			  \[
-				([^\[\]]+)		# link text = $2; can\'t contain [ or ]
-			  \]
-			)
-			}xs',
-			array($this, '_doAnchors_reference_callback'), $text);
-
-		$this->in_anchor = false;
-		return $text;
-	}
-
-	/**
-	 * Callback for reference anchors
-	 * @param  array $matches
-	 * @return string
-	 */
-	protected function _doAnchors_reference_callback($matches) {
-		$whole_match =  $matches[1];
-		$link_text   =  $matches[2];
-		$link_id     =& $matches[3];
-
-		if ($link_id == "") {
-			// for shortcut links like [this][] or [this].
-			$link_id = $link_text;
-		}
-
-		// lower-case and turn embedded newlines into spaces
-		$link_id = strtolower($link_id);
-		$link_id = preg_replace('{[ ]?\n}', ' ', $link_id);
-
-		if (isset($this->urls[$link_id])) {
-			$url = $this->urls[$link_id];
-			$url = $this->encodeURLAttribute($url);
-
-			$result = "titles[$link_id] ) ) {
-				$title = $this->titles[$link_id];
-				$title = $this->encodeAttribute($title);
-				$result .=  " title=\"$title\"";
-			}
-			if (isset($this->ref_attr[$link_id]))
-				$result .= $this->ref_attr[$link_id];
-
-			$link_text = $this->runSpanGamut($link_text);
-			$result .= ">$link_text";
-			$result = $this->hashPart($result);
-		}
-		else {
-			$result = $whole_match;
-		}
-		return $result;
-	}
-
-	/**
-	 * Callback for inline anchors
-	 * @param  array $matches
-	 * @return string
-	 */
-	protected function _doAnchors_inline_callback($matches) {
-		$link_text		=  $this->runSpanGamut($matches[2]);
-		$url			=  $matches[3] === '' ? $matches[4] : $matches[3];
-		$title_quote		=& $matches[6];
-		$title			=& $matches[7];
-		$attr  = $this->doExtraAttributes("a", $dummy =& $matches[8]);
-
-		// if the URL was of the form  it got caught by the HTML
-		// tag parser and hashed. Need to reverse the process before using the URL.
-		$unhashed = $this->unhash($url);
-		if ($unhashed !== $url)
-			$url = preg_replace('/^<(.*)>$/', '\1', $unhashed);
-
-		$url = $this->encodeURLAttribute($url);
-
-		$result = "encodeAttribute($title);
-			$result .=  " title=\"$title\"";
-		}
-		$result .= $attr;
-
-		$link_text = $this->runSpanGamut($link_text);
-		$result .= ">$link_text";
-
-		return $this->hashPart($result);
-	}
-
-	/**
-	 * Turn Markdown image shortcuts into  tags.
-	 * @param  string $text
-	 * @return string
-	 */
-	protected function doImages($text) {
-		// First, handle reference-style labeled images: ![alt text][id]
-		$text = preg_replace_callback('{
-			(				# wrap whole match in $1
-			  !\[
-				(' . $this->nested_brackets_re . ')		# alt text = $2
-			  \]
-
-			  [ ]?				# one optional space
-			  (?:\n[ ]*)?		# one optional newline followed by spaces
-
-			  \[
-				(.*?)		# id = $3
-			  \]
-
-			)
-			}xs',
-			array($this, '_doImages_reference_callback'), $text);
-
-		// Next, handle inline images:  ![alt text](url "optional title")
-		// Don't forget: encode * and _
-		$text = preg_replace_callback('{
-			(				# wrap whole match in $1
-			  !\[
-				(' . $this->nested_brackets_re . ')		# alt text = $2
-			  \]
-			  \s?			# One optional whitespace character
-			  \(			# literal paren
-				[ \n]*
-				(?:
-					<(\S*)>	# src url = $3
-				|
-					(' . $this->nested_url_parenthesis_re . ')	# src url = $4
-				)
-				[ \n]*
-				(			# $5
-				  ([\'"])	# quote char = $6
-				  (.*?)		# title = $7
-				  \6		# matching quote
-				  [ \n]*
-				)?			# title is optional
-			  \)
-			  (?:[ ]? ' . $this->id_class_attr_catch_re . ' )?	 # $8 = id/class attributes
-			)
-			}xs',
-			array($this, '_doImages_inline_callback'), $text);
-
-		return $text;
-	}
-
-	/**
-	 * Callback for referenced images
-	 * @param  array $matches
-	 * @return string
-	 */
-	protected function _doImages_reference_callback($matches) {
-		$whole_match = $matches[1];
-		$alt_text    = $matches[2];
-		$link_id     = strtolower($matches[3]);
-
-		if ($link_id === "") {
-			$link_id = strtolower($alt_text); // for shortcut links like ![this][].
-		}
-
-		$alt_text = $this->encodeAttribute($alt_text);
-		if (isset($this->urls[$link_id])) {
-			$url = $this->encodeURLAttribute($this->urls[$link_id]);
-			$result = "\"$alt_text\"";titles[$link_id])) {
-				$title = $this->titles[$link_id];
-				$title = $this->encodeAttribute($title);
-				$result .=  " title=\"$title\"";
-			}
-			if (isset($this->ref_attr[$link_id])) {
-				$result .= $this->ref_attr[$link_id];
-			}
-			$result .= $this->empty_element_suffix;
-			$result = $this->hashPart($result);
-		}
-		else {
-			// If there's no such link ID, leave intact:
-			$result = $whole_match;
-		}
-
-		return $result;
-	}
-
-	/**
-	 * Callback for inline images
-	 * @param  array $matches
-	 * @return string
-	 */
-	protected function _doImages_inline_callback($matches) {
-		$alt_text		= $matches[2];
-		$url			= $matches[3] === '' ? $matches[4] : $matches[3];
-		$title_quote		=& $matches[6];
-		$title			=& $matches[7];
-		$attr  = $this->doExtraAttributes("img", $dummy =& $matches[8]);
-
-		$alt_text = $this->encodeAttribute($alt_text);
-		$url = $this->encodeURLAttribute($url);
-		$result = "\"$alt_text\"";encodeAttribute($title);
-			$result .=  " title=\"$title\""; // $title already quoted
-		}
-		$result .= $attr;
-		$result .= $this->empty_element_suffix;
-
-		return $this->hashPart($result);
-	}
-
-	/**
-	 * Process markdown headers. Redefined to add ID and class attribute support.
-	 * @param  string $text
-	 * @return string
-	 */
-	protected function doHeaders($text) {
-		// Setext-style headers:
-		//  Header 1  {#header1}
-		//	  ========
-		//
-		//	  Header 2  {#header2 .class1 .class2}
-		//	  --------
-		//
-		$text = preg_replace_callback(
-			'{
-				(^.+?)								# $1: Header text
-				(?:[ ]+ ' . $this->id_class_attr_catch_re . ' )?	 # $3 = id/class attributes
-				[ ]*\n(=+|-+)[ ]*\n+				# $3: Header footer
-			}mx',
-			array($this, '_doHeaders_callback_setext'), $text);
-
-		// atx-style headers:
-		//	# Header 1        {#header1}
-		//	## Header 2       {#header2}
-		//	## Header 2 with closing hashes ##  {#header3.class1.class2}
-		//	...
-		//	###### Header 6   {.class2}
-		//
-		$text = preg_replace_callback('{
-				^(\#{1,6})	# $1 = string of #\'s
-				[ ]'.($this->hashtag_protection ? '+' : '*').'
-				(.+?)		# $2 = Header text
-				[ ]*
-				\#*			# optional closing #\'s (not counted)
-				(?:[ ]+ ' . $this->id_class_attr_catch_re . ' )?	 # $3 = id/class attributes
-				[ ]*
-				\n+
-			}xm',
-			array($this, '_doHeaders_callback_atx'), $text);
-
-		return $text;
-	}
-
-	/**
-	 * Callback for setext headers
-	 * @param  array $matches
-	 * @return string
-	 */
-	protected function _doHeaders_callback_setext($matches) {
-		if ($matches[3] === '-' && preg_match('{^- }', $matches[1])) {
-			return $matches[0];
-		}
-
-		$level = $matches[3][0] === '=' ? 1 : 2;
-
-		$defaultId = is_callable($this->header_id_func) ? call_user_func($this->header_id_func, $matches[1]) : null;
-
-		$attr  = $this->doExtraAttributes("h$level", $dummy =& $matches[2], $defaultId);
-		$block = "" . $this->runSpanGamut($matches[1]) . "";
-		return "\n" . $this->hashBlock($block) . "\n\n";
-	}
-
-	/**
-	 * Callback for atx headers
-	 * @param  array $matches
-	 * @return string
-	 */
-	protected function _doHeaders_callback_atx($matches) {
-		$level = strlen($matches[1]);
-
-		$defaultId = is_callable($this->header_id_func) ? call_user_func($this->header_id_func, $matches[2]) : null;
-		$attr  = $this->doExtraAttributes("h$level", $dummy =& $matches[3], $defaultId);
-		$block = "" . $this->runSpanGamut($matches[2]) . "";
-		return "\n" . $this->hashBlock($block) . "\n\n";
-	}
-
-	/**
-	 * Form HTML tables.
-	 * @param  string $text
-	 * @return string
-	 */
-	protected function doTables($text) {
-		$less_than_tab = $this->tab_width - 1;
-		// Find tables with leading pipe.
-		//
-		//	| Header 1 | Header 2
-		//	| -------- | --------
-		//	| Cell 1   | Cell 2
-		//	| Cell 3   | Cell 4
-		$text = preg_replace_callback('
-			{
-				^							# Start of a line
-				[ ]{0,' . $less_than_tab . '}	# Allowed whitespace.
-				[|]							# Optional leading pipe (present)
-				(.+) \n						# $1: Header row (at least one pipe)
-
-				[ ]{0,' . $less_than_tab . '}	# Allowed whitespace.
-				[|] ([ ]*[-:]+[-| :]*) \n	# $2: Header underline
-
-				(							# $3: Cells
-					(?>
-						[ ]*				# Allowed whitespace.
-						[|] .* \n			# Row content.
-					)*
-				)
-				(?=\n|\Z)					# Stop at final double newline.
-			}xm',
-			array($this, '_doTable_leadingPipe_callback'), $text);
-
-		// Find tables without leading pipe.
-		//
-		//	Header 1 | Header 2
-		//	-------- | --------
-		//	Cell 1   | Cell 2
-		//	Cell 3   | Cell 4
-		$text = preg_replace_callback('
-			{
-				^							# Start of a line
-				[ ]{0,' . $less_than_tab . '}	# Allowed whitespace.
-				(\S.*[|].*) \n				# $1: Header row (at least one pipe)
-
-				[ ]{0,' . $less_than_tab . '}	# Allowed whitespace.
-				([-:]+[ ]*[|][-| :]*) \n	# $2: Header underline
-
-				(							# $3: Cells
-					(?>
-						.* [|] .* \n		# Row content
-					)*
-				)
-				(?=\n|\Z)					# Stop at final double newline.
-			}xm',
-			array($this, '_DoTable_callback'), $text);
-
-		return $text;
-	}
-
-	/**
-	 * Callback for removing the leading pipe for each row
-	 * @param  array $matches
-	 * @return string
-	 */
-	protected function _doTable_leadingPipe_callback($matches) {
-		$head		= $matches[1];
-		$underline	= $matches[2];
-		$content	= $matches[3];
-
-		$content	= preg_replace('/^ *[|]/m', '', $content);
-
-		return $this->_doTable_callback(array($matches[0], $head, $underline, $content));
-	}
-
-	/**
-	 * Make the align attribute in a table
-	 * @param  string $alignname
-	 * @return string
-	 */
-	protected function _doTable_makeAlignAttr($alignname) {
-		if (empty($this->table_align_class_tmpl)) {
-			return " align=\"$alignname\"";
-		}
-
-		$classname = str_replace('%%', $alignname, $this->table_align_class_tmpl);
-		return " class=\"$classname\"";
-	}
-
-	/**
-	 * Calback for processing tables
-	 * @param  array $matches
-	 * @return string
-	 */
-	protected function _doTable_callback($matches) {
-		$head		= $matches[1];
-		$underline	= $matches[2];
-		$content	= $matches[3];
-		$attr       = [];
-
-		// Remove any tailing pipes for each line.
-		$head		= preg_replace('/[|] *$/m', '', $head);
-		$underline	= preg_replace('/[|] *$/m', '', $underline);
-		$content	= preg_replace('/[|] *$/m', '', $content);
-
-		// Reading alignement from header underline.
-		$separators	= preg_split('/ *[|] */', $underline);
-		foreach ($separators as $n => $s) {
-			if (preg_match('/^ *-+: *$/', $s))
-				$attr[$n] = $this->_doTable_makeAlignAttr('right');
-			else if (preg_match('/^ *:-+: *$/', $s))
-				$attr[$n] = $this->_doTable_makeAlignAttr('center');
-			else if (preg_match('/^ *:-+ *$/', $s))
-				$attr[$n] = $this->_doTable_makeAlignAttr('left');
-			else
-				$attr[$n] = '';
-		}
-
-		// Parsing span elements, including code spans, character escapes,
-		// and inline HTML tags, so that pipes inside those gets ignored.
-		$head		= $this->parseSpan($head);
-		$headers	= preg_split('/ *[|] */', $head);
-		$col_count	= count($headers);
-		$attr       = array_pad($attr, $col_count, '');
-
-		// Write column headers.
-		$text = "\n";
-		$text .= "\n";
-		$text .= "\n";
-		foreach ($headers as $n => $header) {
-			$text .= "  " . $this->runSpanGamut(trim($header)) . "\n";
-		}
-		$text .= "\n";
-		$text .= "\n";
-
-		// Split content by row.
-		$rows = explode("\n", trim($content, "\n"));
-
-		$text .= "\n";
-		foreach ($rows as $row) {
-			// Parsing span elements, including code spans, character escapes,
-			// and inline HTML tags, so that pipes inside those gets ignored.
-			$row = $this->parseSpan($row);
-
-			// Split row by cell.
-			$row_cells = preg_split('/ *[|] */', $row, $col_count);
-			$row_cells = array_pad($row_cells, $col_count, '');
-
-			$text .= "\n";
-			foreach ($row_cells as $n => $cell) {
-				$text .= "  " . $this->runSpanGamut(trim($cell)) . "\n";
-			}
-			$text .= "\n";
-		}
-		$text .= "\n";
-		$text .= "
    ";
-
-		return $this->hashBlock($text) . "\n";
-	}
-
-	/**
-	 * Form HTML definition lists.
-	 * @param  string $text
-	 * @return string
-	 */
-	protected function doDefLists($text) {
-		$less_than_tab = $this->tab_width - 1;
-
-		// Re-usable pattern to match any entire dl list:
-		$whole_list_re = '(?>
-			(								# $1 = whole list
-			  (								# $2
-				[ ]{0,' . $less_than_tab . '}
-				((?>.*\S.*\n)+)				# $3 = defined term
-				\n?
-				[ ]{0,' . $less_than_tab . '}:[ ]+ # colon starting definition
-			  )
-			  (?s:.+?)
-			  (								# $4
-				  \z
-				|
-				  \n{2,}
-				  (?=\S)
-				  (?!						# Negative lookahead for another term
-					[ ]{0,' . $less_than_tab . '}
-					(?: \S.*\n )+?			# defined term
-					\n?
-					[ ]{0,' . $less_than_tab . '}:[ ]+ # colon starting definition
-				  )
-				  (?!						# Negative lookahead for another definition
-					[ ]{0,' . $less_than_tab . '}:[ ]+ # colon starting definition
-				  )
-			  )
-			)
-		)'; // mx
-
-		$text = preg_replace_callback('{
-				(?>\A\n?|(?<=\n\n))
-				' . $whole_list_re . '
-			}mx',
-			array($this, '_doDefLists_callback'), $text);
-
-		return $text;
-	}
-
-	/**
-	 * Callback for processing definition lists
-	 * @param  array $matches
-	 * @return string
-	 */
-	protected function _doDefLists_callback($matches) {
-		// Re-usable patterns to match list item bullets and number markers:
-		$list = $matches[1];
-
-		// Turn double returns into triple returns, so that we can make a
-		// paragraph for the last item in a list, if necessary:
-		$result = trim($this->processDefListItems($list));
-		$result = "
    \n" . $result . "\n
    ";
-		return $this->hashBlock($result) . "\n\n";
-	}
-
-	/**
-	 * Process the contents of a single definition list, splitting it
-	 * into individual term and definition list items.
-	 * @param  string $list_str
-	 * @return string
-	 */
-	protected function processDefListItems($list_str) {
-
-		$less_than_tab = $this->tab_width - 1;
-
-		// Trim trailing blank lines:
-		$list_str = preg_replace("/\n{2,}\\z/", "\n", $list_str);
-
-		// Process definition terms.
-		$list_str = preg_replace_callback('{
-			(?>\A\n?|\n\n+)						# leading line
-			(									# definition terms = $1
-				[ ]{0,' . $less_than_tab . '}	# leading whitespace
-				(?!\:[ ]|[ ])					# negative lookahead for a definition
-												#   mark (colon) or more whitespace.
-				(?> \S.* \n)+?					# actual term (not whitespace).
-			)
-			(?=\n?[ ]{0,3}:[ ])					# lookahead for following line feed
-												#   with a definition mark.
-			}xm',
-			array($this, '_processDefListItems_callback_dt'), $list_str);
-
-		// Process actual definitions.
-		$list_str = preg_replace_callback('{
-			\n(\n+)?							# leading line = $1
-			(									# marker space = $2
-				[ ]{0,' . $less_than_tab . '}	# whitespace before colon
-				\:[ ]+							# definition mark (colon)
-			)
-			((?s:.+?))							# definition text = $3
-			(?= \n+ 							# stop at next definition mark,
-				(?:								# next term or end of text
-					[ ]{0,' . $less_than_tab . '} \:[ ]	|
-					
     | \z
-				)
-			)
-			}xm',
-			array($this, '_processDefListItems_callback_dd'), $list_str);
-
-		return $list_str;
-	}
-
-	/**
-	 * Callback for 
     elements in definition lists
-	 * @param  array $matches
-	 * @return string
-	 */
-	protected function _processDefListItems_callback_dt($matches) {
-		$terms = explode("\n", trim($matches[1]));
-		$text = '';
-		foreach ($terms as $term) {
-			$term = $this->runSpanGamut(trim($term));
-			$text .= "\n
    " . $term . "
    ";
-		}
-		return $text . "\n";
-	}
-
-	/**
-	 * Callback for 
     elements in definition lists
-	 * @param  array $matches
-	 * @return string
-	 */
-	protected function _processDefListItems_callback_dd($matches) {
-		$leading_line	= $matches[1];
-		$marker_space	= $matches[2];
-		$def			= $matches[3];
-
-		if ($leading_line || preg_match('/\n{2,}/', $def)) {
-			// Replace marker with the appropriate whitespace indentation
-			$def = str_repeat(' ', strlen($marker_space)) . $def;
-			$def = $this->runBlockGamut($this->outdent($def . "\n\n"));
-			$def = "\n". $def ."\n";
-		}
-		else {
-			$def = rtrim($def);
-			$def = $this->runSpanGamut($this->outdent($def));
-		}
-
-		return "\n
    " . $def . "
    \n";
-	}
-
-	/**
-	 * Adding the fenced code block syntax to regular Markdown:
-	 *
-	 * ~~~
-	 * Code block
-	 * ~~~
-	 *
-	 * @param  string $text
-	 * @return string
-	 */
-	protected function doFencedCodeBlocks($text) {
-
-		$text = preg_replace_callback('{
-				(?:\n|\A)
-				# 1: Opening marker
-				(
-					(?:~{3,}|`{3,}) # 3 or more tildes/backticks.
-				)
-				[ ]*
-				(?:
-					\.?([-_:a-zA-Z0-9]+) # 2: standalone class name
-				)?
-				[ ]*
-				(?:
-					' . $this->id_class_attr_catch_re . ' # 3: Extra attributes
-				)?
-				[ ]* \n # Whitespace and newline following marker.
-
-				# 4: Content
-				(
-					(?>
-						(?!\1 [ ]* \n)	# Not a closing marker.
-						.*\n+
-					)+
-				)
-
-				# Closing marker.
-				\1 [ ]* (?= \n )
-			}xm',
-			array($this, '_doFencedCodeBlocks_callback'), $text);
-
-		return $text;
-	}
-
-	/**
-	 * Callback to process fenced code blocks
-	 * @param  array $matches
-	 * @return string
-	 */
-	protected function _doFencedCodeBlocks_callback($matches) {
-		$classname =& $matches[2];
-		$attrs     =& $matches[3];
-		$codeblock = $matches[4];
-
-		if ($this->code_block_content_func) {
-			$codeblock = call_user_func($this->code_block_content_func, $codeblock, $classname);
-		} else {
-			$codeblock = htmlspecialchars($codeblock, ENT_NOQUOTES);
-		}
-
-		$codeblock = preg_replace_callback('/^\n+/',
-			array($this, '_doFencedCodeBlocks_newlines'), $codeblock);
-
-		$classes = array();
-		if ($classname !== "") {
-			if ($classname[0] === '.') {
-				$classname = substr($classname, 1);
-			}
-			$classes[] = $this->code_class_prefix . $classname;
-		}
-		$attr_str = $this->doExtraAttributes($this->code_attr_on_pre ? "pre" : "code", $attrs, null, $classes);
-		$pre_attr_str  = $this->code_attr_on_pre ? $attr_str : '';
-		$code_attr_str = $this->code_attr_on_pre ? '' : $attr_str;
-		$codeblock  = "$codeblock
    ";
-
-		return "\n\n".$this->hashBlock($codeblock)."\n\n";
-	}
-
-	/**
-	 * Replace new lines in fenced code blocks
-	 * @param  array $matches
-	 * @return string
-	 */
-	protected function _doFencedCodeBlocks_newlines($matches) {
-		return str_repeat("empty_element_suffix",
-			strlen($matches[0]));
-	}
-
-	/**
-	 * Redefining emphasis markers so that emphasis by underscore does not
-	 * work in the middle of a word.
-	 * @var array
-	 */
-	protected $em_relist = array(
-		''  => '(?:(? '(? '(? '(?:(? '(? '(? '(?:(? '(? '(? tags
-	 * @return string       HTML output
-	 */
-	protected function formParagraphs($text, $wrap_in_p = true) {
-		// Strip leading and trailing lines:
-		$text = preg_replace('/\A\n+|\n+\z/', '', $text);
-
-		$grafs = preg_split('/\n{2,}/', $text, -1, PREG_SPLIT_NO_EMPTY);
-
-		// Wrap 
     tags and unhashify HTML blocks
-		foreach ($grafs as $key => $value) {
-			$value = trim($this->runSpanGamut($value));
-
-			// Check if this should be enclosed in a paragraph.
-			// Clean tag hashes & block tag hashes are left alone.
-			$is_p = $wrap_in_p && !preg_match('/^B\x1A[0-9]+B|^C\x1A[0-9]+C$/', $value);
-
-			if ($is_p) {
-				$value = "
    $value
    ";
-			}
-			$grafs[$key] = $value;
-		}
-
-		// Join grafs in one text, then unhash HTML tags.
-		$text = implode("\n\n", $grafs);
-
-		// Finish by removing any tag hashes still present in $text.
-		$text = $this->unhash($text);
-
-		return $text;
-	}
-
-
-	/**
-	 * Footnotes - Strips link definitions from text, stores the URLs and
-	 * titles in hash references.
-	 * @param  string $text
-	 * @return string
-	 */
-	protected function stripFootnotes($text) {
-		$less_than_tab = $this->tab_width - 1;
-
-		// Link defs are in the form: [^id]: url "optional title"
-		$text = preg_replace_callback('{
-			^[ ]{0,' . $less_than_tab . '}\[\^(.+?)\][ ]?:	# note_id = $1
-			  [ ]*
-			  \n?					# maybe *one* newline
-			(						# text = $2 (no blank lines allowed)
-				(?:
-					.+				# actual text
-				|
-					\n				# newlines but
-					(?!\[.+?\][ ]?:\s)# negative lookahead for footnote or link definition marker.
-					(?!\n+[ ]{0,3}\S)# ensure line is not blank and followed
-									# by non-indented content
-				)*
-			)
-			}xm',
-			array($this, '_stripFootnotes_callback'),
-			$text);
-		return $text;
-	}
-
-	/**
-	 * Callback for stripping footnotes
-	 * @param  array $matches
-	 * @return string
-	 */
-	protected function _stripFootnotes_callback($matches) {
-		$note_id = $this->fn_id_prefix . $matches[1];
-		$this->footnotes[$note_id] = $this->outdent($matches[2]);
-		return ''; // String that will replace the block
-	}
-
-	/**
-	 * Replace footnote references in $text [^id] with a special text-token
-	 * which will be replaced by the actual footnote marker in appendFootnotes.
-	 * @param  string $text
-	 * @return string
-	 */
-	protected function doFootnotes($text) {
-		if (!$this->in_anchor) {
-			$text = preg_replace('{\[\^(.+?)\]}', "F\x1Afn:\\1\x1A:", $text);
-		}
-		return $text;
-	}
-
-	/**
-	 * Append footnote list to text
-	 * @param  string $text
-	 * @return string
-	 */
-	protected function appendFootnotes($text) {
-		$text = preg_replace_callback('{F\x1Afn:(.*?)\x1A:}',
-			array($this, '_appendFootnotes_callback'), $text);
-
-		if ( ! empty( $this->footnotes_ordered ) ) {
-			$this->_doFootnotes();
-			if ( ! $this->omit_footnotes ) {
-				$text .= "\n\n";
-				$text .= "
    \n";
-				$text .= "empty_element_suffix . "\n";
-				$text .= $this->footnotes_assembled;
-				$text .= "
    ";
-			}
-		}
-		return $text;
-	}
-
-
-	/**
-	 * Generates the HTML for footnotes.  Called by appendFootnotes, even if
-	 * footnotes are not being appended.
-	 * @return void
-	 */
-	protected function _doFootnotes() {
-		$attr = array();
-		if ($this->fn_backlink_class !== "") {
-			$class = $this->fn_backlink_class;
-			$class = $this->encodeAttribute($class);
-			$attr['class'] = " class=\"$class\"";
-		}
-		$attr['role'] = " role=\"doc-backlink\"";
-		$num = 0;
-
-		$text = "
      \n\n";
-		while (!empty($this->footnotes_ordered)) {
-			$footnote = reset($this->footnotes_ordered);
-			$note_id = key($this->footnotes_ordered);
-			unset($this->footnotes_ordered[$note_id]);
-			$ref_count = $this->footnotes_ref_count[$note_id];
-			unset($this->footnotes_ref_count[$note_id]);
-			unset($this->footnotes[$note_id]);
-
-			$footnote .= "\n"; // Need to append newline before parsing.
-			$footnote = $this->runBlockGamut("$footnote\n");
-			$footnote = preg_replace_callback('{F\x1Afn:(.*?)\x1A:}',
-				array($this, '_appendFootnotes_callback'), $footnote);
-
-			$num++;
-			$note_id = $this->encodeAttribute($note_id);
-
-			// Prepare backlink, multiple backlinks if multiple references
-			// Do not create empty backlinks if the html is blank
-			$backlink = "";
-			if (!empty($this->fn_backlink_html)) {
-				for ($ref_num = 1; $ref_num <= $ref_count; ++$ref_num) {
-					if (!empty($this->fn_backlink_title)) {
-						$attr['title'] = ' title="' . $this->encodeAttribute($this->fn_backlink_title) . '"';
-					}
-					if (!empty($this->fn_backlink_label)) {
-						$attr['label'] = ' aria-label="' . $this->encodeAttribute($this->fn_backlink_label) . '"';
-					}
-					$parsed_attr = $this->parseFootnotePlaceholders(
-						implode('', $attr),
-						$num,
-						$ref_num
-					);
-					$backlink_text = $this->parseFootnotePlaceholders(
-						$this->fn_backlink_html,
-						$num,
-						$ref_num
-					);
-					$ref_count_mark = $ref_num > 1 ? $ref_num : '';
-					$backlink .= " $backlink_text";
-				}
-				$backlink = trim($backlink);
-			}
-
-			// Add backlink to last paragraph; create new paragraph if needed.
-			if (!empty($backlink)) {
-				if (preg_match('{
      $}', $footnote)) {
-					$footnote = substr($footnote, 0, -4) . " $backlink
      ";
-				} else {
-					$footnote .= "\n\n
      $backlink
      ";
-				}
-			}
-
-			$text .= "
    1. \n";
-			$text .= $footnote . "\n";
-			$text .= "
      2. \n\n";
-		}
-		$text .= "
    \n";
-
-		$this->footnotes_assembled = $text;
-	}
-
-	/**
-	 * Callback for appending footnotes
-	 * @param  array $matches
-	 * @return string
-	 */
-	protected function _appendFootnotes_callback($matches) {
-		$node_id = $this->fn_id_prefix . $matches[1];
-
-		// Create footnote marker only if it has a corresponding footnote *and*
-		// the footnote hasn't been used by another marker.
-		if (isset($this->footnotes[$node_id])) {
-			$num =& $this->footnotes_numbers[$node_id];
-			if (!isset($num)) {
-				// Transfer footnote content to the ordered list and give it its
-				// number
-				$this->footnotes_ordered[$node_id] = $this->footnotes[$node_id];
-				$this->footnotes_ref_count[$node_id] = 1;
-				$num = $this->footnote_counter++;
-				$ref_count_mark = '';
-			} else {
-				$ref_count_mark = $this->footnotes_ref_count[$node_id] += 1;
-			}
-
-			$attr = "";
-			if ($this->fn_link_class !== "") {
-				$class = $this->fn_link_class;
-				$class = $this->encodeAttribute($class);
-				$attr .= " class=\"$class\"";
-			}
-			if ($this->fn_link_title !== "") {
-				$title = $this->fn_link_title;
-				$title = $this->encodeAttribute($title);
-				$attr .= " title=\"$title\"";
-			}
-			$attr .= " role=\"doc-noteref\"";
-
-			$attr = str_replace("%%", $num, $attr);
-			$node_id = $this->encodeAttribute($node_id);
-
-			return
-				"".
-				"$num".
-				"";
-		}
-
-		return "[^" . $matches[1] . "]";
-	}
-
-	/**
-	 * Build footnote label by evaluating any placeholders.
-	 * - ^^  footnote number
-	 * - %%  footnote reference number (Nth reference to footnote number)
-	 * @param  string $label
-	 * @param  int    $footnote_number
-	 * @param  int    $reference_number
-	 * @return string
-	 */
-	protected function parseFootnotePlaceholders($label, $footnote_number, $reference_number) {
-		return str_replace(
-			array('^^', '%%'),
-			array($footnote_number, $reference_number),
-			$label
-		);
-	}
-
-
-	/**
-	 * Abbreviations - strips abbreviations from text, stores titles in hash
-	 * references.
-	 * @param  string $text
-	 * @return string
-	 */
-	protected function stripAbbreviations($text) {
-		$less_than_tab = $this->tab_width - 1;
-
-		// Link defs are in the form: [id]*: url "optional title"
-		$text = preg_replace_callback('{
-			^[ ]{0,' . $less_than_tab . '}\*\[(.+?)\][ ]?:	# abbr_id = $1
-			(.*)					# text = $2 (no blank lines allowed)
-			}xm',
-			array($this, '_stripAbbreviations_callback'),
-			$text);
-		return $text;
-	}
-
-	/**
-	 * Callback for stripping abbreviations
-	 * @param  array $matches
-	 * @return string
-	 */
-	protected function _stripAbbreviations_callback($matches) {
-		$abbr_word = $matches[1];
-		$abbr_desc = $matches[2];
-		if ($this->abbr_word_re) {
-			$this->abbr_word_re .= '|';
-		}
-		$this->abbr_word_re .= preg_quote($abbr_word);
-		$this->abbr_desciptions[$abbr_word] = trim($abbr_desc);
-		return ''; // String that will replace the block
-	}
-
-	/**
-	 * Find defined abbreviations in text and wrap them in  elements.
-	 * @param  string $text
-	 * @return string
-	 */
-	protected function doAbbreviations($text) {
-		if ($this->abbr_word_re) {
-			// cannot use the /x modifier because abbr_word_re may
-			// contain significant spaces:
-			$text = preg_replace_callback('{' .
-				'(?abbr_word_re . ')' .
-				'(?![\w\x1A])' .
-				'}',
-				array($this, '_doAbbreviations_callback'), $text);
-		}
-		return $text;
-	}
-
-	/**
-	 * Callback for processing abbreviations
-	 * @param  array $matches
-	 * @return string
-	 */
-	protected function _doAbbreviations_callback($matches) {
-		$abbr = $matches[0];
-		if (isset($this->abbr_desciptions[$abbr])) {
-			$desc = $this->abbr_desciptions[$abbr];
-			if (empty($desc)) {
-				return $this->hashPart("$abbr");
-			}
-			$desc = $this->encodeAttribute($desc);
-			return $this->hashPart("$abbr");
-		}
-		return $matches[0];
-	}
-}
diff --git a/lib/michelf/Michelf/MarkdownInterface.inc.php b/lib/michelf/Michelf/MarkdownInterface.inc.php
deleted file mode 100644
index c4e9ac7f64..0000000000
--- a/lib/michelf/Michelf/MarkdownInterface.inc.php
+++ /dev/null
@@ -1,9 +0,0 @@
-
- * @copyright 2004-2021 Michel Fortin 
- * @copyright (Original Markdown) 2004-2006 John Gruber 
- */
-
-namespace Michelf;
-
-/**
- * Markdown Parser Interface
- */
-interface MarkdownInterface {
-	/**
-	 * Initialize the parser and return the result of its transform method.
-	 * This will work fine for derived classes too.
-	 *
-	 * @api
-	 *
-	 * @param  string $text
-	 * @return string
-	 */
-	public static function defaultTransform($text);
-
-	/**
-	 * Main function. Performs some preprocessing on the input text
-	 * and pass it through the document gamut.
-	 *
-	 * @api
-	 *
-	 * @param  string $text
-	 * @return string
-	 */
-	public function transform($text);
-}
diff --git a/lib/michelf/michelf.class.php b/lib/michelf/michelf.class.php
deleted file mode 100644
index 6f55684fb5..0000000000
--- a/lib/michelf/michelf.class.php
+++ /dev/null
@@ -1,27 +0,0 @@
-fn_id_prefix = "post22-";
-        $html    = $parser->transform($mdCodes);
-
-        return "
    $html
    ";
-    }
-}
diff --git a/lib/parsedownextraplugin/LICENSE.txt b/lib/parsedownextraplugin/LICENSE.txt
new file mode 100644
index 0000000000..8e7c764d16
--- /dev/null
+++ b/lib/parsedownextraplugin/LICENSE.txt
@@ -0,0 +1,20 @@
+The MIT License (MIT)
+
+Copyright (c) 2013-2018 Emanuil Rusev, erusev.com
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software is furnished to do so,
+subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
diff --git a/lib/parsedownextraplugin/index.html b/lib/parsedownextraplugin/index.html
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/lib/parsedownextraplugin/parsedown.php b/lib/parsedownextraplugin/parsedown.php
new file mode 100644
index 0000000000..69147dc2ac
--- /dev/null
+++ b/lib/parsedownextraplugin/parsedown.php
@@ -0,0 +1,1992 @@
+textElements($text);
+
+        # convert to markup
+        $markup = $this->elements($Elements);
+
+        # trim line breaks
+        $markup = trim($markup, "\n");
+
+        return $markup;
+    }
+
+    protected function textElements($text)
+    {
+        # make sure no definitions are set
+        $this->DefinitionData = array();
+
+        # standardize line breaks
+        $text = str_replace(array("\r\n", "\r"), "\n", $text);
+
+        # remove surrounding line breaks
+        $text = trim($text, "\n");
+
+        # split text into lines
+        $lines = explode("\n", $text);
+
+        # iterate through lines to identify blocks
+        return $this->linesElements($lines);
+    }
+
+    #
+    # Setters
+    #
+
+    function setBreaksEnabled($breaksEnabled)
+    {
+        $this->breaksEnabled = $breaksEnabled;
+
+        return $this;
+    }
+
+    protected $breaksEnabled;
+
+    function setMarkupEscaped($markupEscaped)
+    {
+        $this->markupEscaped = $markupEscaped;
+
+        return $this;
+    }
+
+    protected $markupEscaped;
+
+    function setUrlsLinked($urlsLinked)
+    {
+        $this->urlsLinked = $urlsLinked;
+
+        return $this;
+    }
+
+    protected $urlsLinked = true;
+
+    function setSafeMode($safeMode)
+    {
+        $this->safeMode = (bool) $safeMode;
+
+        return $this;
+    }
+
+    protected $safeMode;
+
+    function setStrictMode($strictMode)
+    {
+        $this->strictMode = (bool) $strictMode;
+
+        return $this;
+    }
+
+    protected $strictMode;
+
+    protected $safeLinksWhitelist = array(
+        'http://',
+        'https://',
+        'ftp://',
+        'ftps://',
+        'mailto:',
+        'tel:',
+        'data:image/png;base64,',
+        'data:image/gif;base64,',
+        'data:image/jpeg;base64,',
+        'irc:',
+        'ircs:',
+        'git:',
+        'ssh:',
+        'news:',
+        'steam:',
+    );
+
+    #
+    # Lines
+    #
+
+    protected $BlockTypes = array(
+        '#' => array('Header'),
+        '*' => array('Rule', 'List'),
+        '+' => array('List'),
+        '-' => array('SetextHeader', 'Table', 'Rule', 'List'),
+        '0' => array('List'),
+        '1' => array('List'),
+        '2' => array('List'),
+        '3' => array('List'),
+        '4' => array('List'),
+        '5' => array('List'),
+        '6' => array('List'),
+        '7' => array('List'),
+        '8' => array('List'),
+        '9' => array('List'),
+        ':' => array('Table'),
+        '<' => array('Comment', 'Markup'),
+        '=' => array('SetextHeader'),
+        '>' => array('Quote'),
+        '[' => array('Reference'),
+        '_' => array('Rule'),
+        '`' => array('FencedCode'),
+        '|' => array('Table'),
+        '~' => array('FencedCode'),
+    );
+
+    # ~
+
+    protected $unmarkedBlockTypes = array(
+        'Code',
+    );
+
+    #
+    # Blocks
+    #
+
+    protected function lines(array $lines)
+    {
+        return $this->elements($this->linesElements($lines));
+    }
+
+    protected function linesElements(array $lines)
+    {
+        $Elements = array();
+        $CurrentBlock = null;
+
+        foreach ($lines as $line)
+        {
+            if (chop($line) === '')
+            {
+                if (isset($CurrentBlock))
+                {
+                    $CurrentBlock['interrupted'] = (isset($CurrentBlock['interrupted'])
+                        ? $CurrentBlock['interrupted'] + 1 : 1
+                    );
+                }
+
+                continue;
+            }
+
+            while (($beforeTab = strstr($line, "\t", true)) !== false)
+            {
+                $shortage = 4 - mb_strlen($beforeTab, 'utf-8') % 4;
+
+                $line = $beforeTab
+                    . str_repeat(' ', $shortage)
+                    . substr($line, strlen($beforeTab) + 1)
+                ;
+            }
+
+            $indent = strspn($line, ' ');
+
+            $text = $indent > 0 ? substr($line, $indent) : $line;
+
+            # ~
+
+            $Line = array('body' => $line, 'indent' => $indent, 'text' => $text);
+
+            # ~
+
+            if (isset($CurrentBlock['continuable']))
+            {
+                $methodName = 'block' . $CurrentBlock['type'] . 'Continue';
+                $Block = $this->$methodName($Line, $CurrentBlock);
+
+                if (isset($Block))
+                {
+                    $CurrentBlock = $Block;
+
+                    continue;
+                }
+                else
+                {
+                    if ($this->isBlockCompletable($CurrentBlock['type']))
+                    {
+                        $methodName = 'block' . $CurrentBlock['type'] . 'Complete';
+                        $CurrentBlock = $this->$methodName($CurrentBlock);
+                    }
+                }
+            }
+
+            # ~
+
+            $marker = $text[0];
+
+            # ~
+
+            $blockTypes = $this->unmarkedBlockTypes;
+
+            if (isset($this->BlockTypes[$marker]))
+            {
+                foreach ($this->BlockTypes[$marker] as $blockType)
+                {
+                    $blockTypes []= $blockType;
+                }
+            }
+
+            #
+            # ~
+
+            foreach ($blockTypes as $blockType)
+            {
+                $Block = $this->{"block$blockType"}($Line, $CurrentBlock);
+
+                if (isset($Block))
+                {
+                    $Block['type'] = $blockType;
+
+                    if ( ! isset($Block['identified']))
+                    {
+                        if (isset($CurrentBlock))
+                        {
+                            $Elements[] = $this->extractElement($CurrentBlock);
+                        }
+
+                        $Block['identified'] = true;
+                    }
+
+                    if ($this->isBlockContinuable($blockType))
+                    {
+                        $Block['continuable'] = true;
+                    }
+
+                    $CurrentBlock = $Block;
+
+                    continue 2;
+                }
+            }
+
+            # ~
+
+            if (isset($CurrentBlock) and $CurrentBlock['type'] === 'Paragraph')
+            {
+                $Block = $this->paragraphContinue($Line, $CurrentBlock);
+            }
+
+            if (isset($Block))
+            {
+                $CurrentBlock = $Block;
+            }
+            else
+            {
+                if (isset($CurrentBlock))
+                {
+                    $Elements[] = $this->extractElement($CurrentBlock);
+                }
+
+                $CurrentBlock = $this->paragraph($Line);
+
+                $CurrentBlock['identified'] = true;
+            }
+        }
+
+        # ~
+
+        if (isset($CurrentBlock['continuable']) and $this->isBlockCompletable($CurrentBlock['type']))
+        {
+            $methodName = 'block' . $CurrentBlock['type'] . 'Complete';
+            $CurrentBlock = $this->$methodName($CurrentBlock);
+        }
+
+        # ~
+
+        if (isset($CurrentBlock))
+        {
+            $Elements[] = $this->extractElement($CurrentBlock);
+        }
+
+        # ~
+
+        return $Elements;
+    }
+
+    protected function extractElement(array $Component)
+    {
+        if ( ! isset($Component['element']))
+        {
+            if (isset($Component['markup']))
+            {
+                $Component['element'] = array('rawHtml' => $Component['markup']);
+            }
+            elseif (isset($Component['hidden']))
+            {
+                $Component['element'] = array();
+            }
+        }
+
+        return $Component['element'];
+    }
+
+    protected function isBlockContinuable($Type)
+    {
+        return method_exists($this, 'block' . $Type . 'Continue');
+    }
+
+    protected function isBlockCompletable($Type)
+    {
+        return method_exists($this, 'block' . $Type . 'Complete');
+    }
+
+    #
+    # Code
+
+    protected function blockCode($Line, $Block = null)
+    {
+        if (isset($Block) and $Block['type'] === 'Paragraph' and ! isset($Block['interrupted']))
+        {
+            return;
+        }
+
+        if ($Line['indent'] >= 4)
+        {
+            $text = substr($Line['body'], 4);
+
+            $Block = array(
+                'element' => array(
+                    'name' => 'pre',
+                    'element' => array(
+                        'name' => 'code',
+                        'text' => $text,
+                    ),
+                ),
+            );
+
+            return $Block;
+        }
+    }
+
+    protected function blockCodeContinue($Line, $Block)
+    {
+        if ($Line['indent'] >= 4)
+        {
+            if (isset($Block['interrupted']))
+            {
+                $Block['element']['element']['text'] .= str_repeat("\n", $Block['interrupted']);
+
+                unset($Block['interrupted']);
+            }
+
+            $Block['element']['element']['text'] .= "\n";
+
+            $text = substr($Line['body'], 4);
+
+            $Block['element']['element']['text'] .= $text;
+
+            return $Block;
+        }
+    }
+
+    protected function blockCodeComplete($Block)
+    {
+        return $Block;
+    }
+
+    #
+    # Comment
+
+    protected function blockComment($Line)
+    {
+        if ($this->markupEscaped or $this->safeMode)
+        {
+            return;
+        }
+
+        if (strpos($Line['text'], '') !== false)
+            {
+                $Block['closed'] = true;
+            }
+
+            return $Block;
+        }
+    }
+
+    protected function blockCommentContinue($Line, array $Block)
+    {
+        if (isset($Block['closed']))
+        {
+            return;
+        }
+
+        $Block['element']['rawHtml'] .= "\n" . $Line['body'];
+
+        if (strpos($Line['text'], '-->') !== false)
+        {
+            $Block['closed'] = true;
+        }
+
+        return $Block;
+    }
+
+    #
+    # Fenced Code
+
+    protected function blockFencedCode($Line)
+    {
+        $marker = $Line['text'][0];
+
+        $openerLength = strspn($Line['text'], $marker);
+
+        if ($openerLength < 3)
+        {
+            return;
+        }
+
+        $infostring = trim(substr($Line['text'], $openerLength), "\t ");
+
+        if (strpos($infostring, '`') !== false)
+        {
+            return;
+        }
+
+        $Element = array(
+            'name' => 'code',
+            'text' => '',
+        );
+
+        if ($infostring !== '')
+        {
+            /**
+             * https://www.w3.org/TR/2011/WD-html5-20110525/elements.html#classes
+             * Every HTML element may have a class attribute specified.
+             * The attribute, if specified, must have a value that is a set
+             * of space-separated tokens representing the various classes
+             * that the element belongs to.
+             * [...]
+             * The space characters, for the purposes of this specification,
+             * are U+0020 SPACE, U+0009 CHARACTER TABULATION (tab),
+             * U+000A LINE FEED (LF), U+000C FORM FEED (FF), and
+             * U+000D CARRIAGE RETURN (CR).
+             */
+            $language = substr($infostring, 0, strcspn($infostring, " \t\n\f\r"));
+
+            $Element['attributes'] = array('class' => "language-$language");
+        }
+
+        $Block = array(
+            'char' => $marker,
+            'openerLength' => $openerLength,
+            'element' => array(
+                'name' => 'pre',
+                'element' => $Element,
+            ),
+        );
+
+        return $Block;
+    }
+
+    protected function blockFencedCodeContinue($Line, $Block)
+    {
+        if (isset($Block['complete']))
+        {
+            return;
+        }
+
+        if (isset($Block['interrupted']))
+        {
+            $Block['element']['element']['text'] .= str_repeat("\n", $Block['interrupted']);
+
+            unset($Block['interrupted']);
+        }
+
+        if (($len = strspn($Line['text'], $Block['char'])) >= $Block['openerLength']
+            and chop(substr($Line['text'], $len), ' ') === ''
+        ) {
+            $Block['element']['element']['text'] = substr($Block['element']['element']['text'], 1);
+
+            $Block['complete'] = true;
+
+            return $Block;
+        }
+
+        $Block['element']['element']['text'] .= "\n" . $Line['body'];
+
+        return $Block;
+    }
+
+    protected function blockFencedCodeComplete($Block)
+    {
+        return $Block;
+    }
+
+    #
+    # Header
+
+    protected function blockHeader($Line)
+    {
+        $level = strspn($Line['text'], '#');
+
+        if ($level > 6)
+        {
+            return;
+        }
+
+        $text = trim($Line['text'], '#');
+
+        if ($this->strictMode and isset($text[0]) and $text[0] !== ' ')
+        {
+            return;
+        }
+
+        $text = trim($text, ' ');
+
+        $Block = array(
+            'element' => array(
+                'name' => 'h' . $level,
+                'handler' => array(
+                    'function' => 'lineElements',
+                    'argument' => $text,
+                    'destination' => 'elements',
+                )
+            ),
+        );
+
+        return $Block;
+    }
+
+    #
+    # List
+
+    protected function blockList($Line, array $CurrentBlock = null)
+    {
+        list($name, $pattern) = $Line['text'][0] <= '-' ? array('ul', '[*+-]') : array('ol', '[0-9]{1,9}+[.\)]');
+
+        if (preg_match('/^('.$pattern.'([ ]++|$))(.*+)/', $Line['text'], $matches))
+        {
+            $contentIndent = strlen($matches[2]);
+
+            if ($contentIndent >= 5)
+            {
+                $contentIndent -= 1;
+                $matches[1] = substr($matches[1], 0, -$contentIndent);
+                $matches[3] = str_repeat(' ', $contentIndent) . $matches[3];
+            }
+            elseif ($contentIndent === 0)
+            {
+                $matches[1] .= ' ';
+            }
+
+            $markerWithoutWhitespace = strstr($matches[1], ' ', true);
+
+            $Block = array(
+                'indent' => $Line['indent'],
+                'pattern' => $pattern,
+                'data' => array(
+                    'type' => $name,
+                    'marker' => $matches[1],
+                    'markerType' => ($name === 'ul' ? $markerWithoutWhitespace : substr($markerWithoutWhitespace, -1)),
+                ),
+                'element' => array(
+                    'name' => $name,
+                    'elements' => array(),
+                ),
+            );
+            $Block['data']['markerTypeRegex'] = preg_quote($Block['data']['markerType'], '/');
+
+            if ($name === 'ol')
+            {
+                $listStart = ltrim(strstr($matches[1], $Block['data']['markerType'], true), '0') ?: '0';
+
+                if ($listStart !== '1')
+                {
+                    if (
+                        isset($CurrentBlock)
+                        and $CurrentBlock['type'] === 'Paragraph'
+                        and ! isset($CurrentBlock['interrupted'])
+                    ) {
+                        return;
+                    }
+
+                    $Block['element']['attributes'] = array('start' => $listStart);
+                }
+            }
+
+            $Block['li'] = array(
+                'name' => 'li',
+                'handler' => array(
+                    'function' => 'li',
+                    'argument' => !empty($matches[3]) ? array($matches[3]) : array(),
+                    'destination' => 'elements'
+                )
+            );
+
+            $Block['element']['elements'] []= & $Block['li'];
+
+            return $Block;
+        }
+    }
+
+    protected function blockListContinue($Line, array $Block)
+    {
+        if (isset($Block['interrupted']) and empty($Block['li']['handler']['argument']))
+        {
+            return null;
+        }
+
+        $requiredIndent = ($Block['indent'] + strlen($Block['data']['marker']));
+
+        if ($Line['indent'] < $requiredIndent
+            and (
+                (
+                    $Block['data']['type'] === 'ol'
+                    and preg_match('/^[0-9]++'.$Block['data']['markerTypeRegex'].'(?:[ ]++(.*)|$)/', $Line['text'], $matches)
+                ) or (
+                    $Block['data']['type'] === 'ul'
+                    and preg_match('/^'.$Block['data']['markerTypeRegex'].'(?:[ ]++(.*)|$)/', $Line['text'], $matches)
+                )
+            )
+        ) {
+            if (isset($Block['interrupted']))
+            {
+                $Block['li']['handler']['argument'] []= '';
+
+                $Block['loose'] = true;
+
+                unset($Block['interrupted']);
+            }
+
+            unset($Block['li']);
+
+            $text = isset($matches[1]) ? $matches[1] : '';
+
+            $Block['indent'] = $Line['indent'];
+
+            $Block['li'] = array(
+                'name' => 'li',
+                'handler' => array(
+                    'function' => 'li',
+                    'argument' => array($text),
+                    'destination' => 'elements'
+                )
+            );
+
+            $Block['element']['elements'] []= & $Block['li'];
+
+            return $Block;
+        }
+        elseif ($Line['indent'] < $requiredIndent and $this->blockList($Line))
+        {
+            return null;
+        }
+
+        if ($Line['text'][0] === '[' and $this->blockReference($Line))
+        {
+            return $Block;
+        }
+
+        if ($Line['indent'] >= $requiredIndent)
+        {
+            if (isset($Block['interrupted']))
+            {
+                $Block['li']['handler']['argument'] []= '';
+
+                $Block['loose'] = true;
+
+                unset($Block['interrupted']);
+            }
+
+            $text = substr($Line['body'], $requiredIndent);
+
+            $Block['li']['handler']['argument'] []= $text;
+
+            return $Block;
+        }
+
+        if ( ! isset($Block['interrupted']))
+        {
+            $text = preg_replace('/^[ ]{0,'.$requiredIndent.'}+/', '', $Line['body']);
+
+            $Block['li']['handler']['argument'] []= $text;
+
+            return $Block;
+        }
+    }
+
+    protected function blockListComplete(array $Block)
+    {
+        if (isset($Block['loose']))
+        {
+            foreach ($Block['element']['elements'] as &$li)
+            {
+                if (end($li['handler']['argument']) !== '')
+                {
+                    $li['handler']['argument'] []= '';
+                }
+            }
+        }
+
+        return $Block;
+    }
+
+    #
+    # Quote
+
+    protected function blockQuote($Line)
+    {
+        if (preg_match('/^>[ ]?+(.*+)/', $Line['text'], $matches))
+        {
+            $Block = array(
+                'element' => array(
+                    'name' => 'blockquote',
+                    'handler' => array(
+                        'function' => 'linesElements',
+                        'argument' => (array) $matches[1],
+                        'destination' => 'elements',
+                    )
+                ),
+            );
+
+            return $Block;
+        }
+    }
+
+    protected function blockQuoteContinue($Line, array $Block)
+    {
+        if (isset($Block['interrupted']))
+        {
+            return;
+        }
+
+        if ($Line['text'][0] === '>' and preg_match('/^>[ ]?+(.*+)/', $Line['text'], $matches))
+        {
+            $Block['element']['handler']['argument'] []= $matches[1];
+
+            return $Block;
+        }
+
+        if ( ! isset($Block['interrupted']))
+        {
+            $Block['element']['handler']['argument'] []= $Line['text'];
+
+            return $Block;
+        }
+    }
+
+    #
+    # Rule
+
+    protected function blockRule($Line)
+    {
+        $marker = $Line['text'][0];
+
+        if (substr_count($Line['text'], $marker) >= 3 and chop($Line['text'], " $marker") === '')
+        {
+            $Block = array(
+                'element' => array(
+                    'name' => 'hr',
+                ),
+            );
+
+            return $Block;
+        }
+    }
+
+    #
+    # Setext
+
+    protected function blockSetextHeader($Line, array $Block = null)
+    {
+        if ( ! isset($Block) or $Block['type'] !== 'Paragraph' or isset($Block['interrupted']))
+        {
+            return;
+        }
+
+        if ($Line['indent'] < 4 and chop(chop($Line['text'], ' '), $Line['text'][0]) === '')
+        {
+            $Block['element']['name'] = $Line['text'][0] === '=' ? 'h1' : 'h2';
+
+            return $Block;
+        }
+    }
+
+    #
+    # Markup
+
+    protected function blockMarkup($Line)
+    {
+        if ($this->markupEscaped or $this->safeMode)
+        {
+            return;
+        }
+
+        if (preg_match('/^<[\/]?+(\w*)(?:[ ]*+'.$this->regexHtmlAttribute.')*+[ ]*+(\/)?>/', $Line['text'], $matches))
+        {
+            $element = strtolower($matches[1]);
+
+            if (in_array($element, $this->textLevelElements))
+            {
+                return;
+            }
+
+            $Block = array(
+                'name' => $matches[1],
+                'element' => array(
+                    'rawHtml' => $Line['text'],
+                    'autobreak' => true,
+                ),
+            );
+
+            return $Block;
+        }
+    }
+
+    protected function blockMarkupContinue($Line, array $Block)
+    {
+        if (isset($Block['closed']) or isset($Block['interrupted']))
+        {
+            return;
+        }
+
+        $Block['element']['rawHtml'] .= "\n" . $Line['body'];
+
+        return $Block;
+    }
+
+    #
+    # Reference
+
+    protected function blockReference($Line)
+    {
+        if (strpos($Line['text'], ']') !== false
+            and preg_match('/^\[(.+?)\]:[ ]*+?(?:[ ]+["\'(](.+)["\')])?[ ]*+$/', $Line['text'], $matches)
+        ) {
+            $id = strtolower($matches[1]);
+
+            $Data = array(
+                'url' => $matches[2],
+                'title' => isset($matches[3]) ? $matches[3] : null,
+            );
+
+            $this->DefinitionData['Reference'][$id] = $Data;
+
+            $Block = array(
+                'element' => array(),
+            );
+
+            return $Block;
+        }
+    }
+
+    #
+    # Table
+
+    protected function blockTable($Line, array $Block = null)
+    {
+        if ( ! isset($Block) or $Block['type'] !== 'Paragraph' or isset($Block['interrupted']))
+        {
+            return;
+        }
+
+        if (
+            strpos($Block['element']['handler']['argument'], '|') === false
+            and strpos($Line['text'], '|') === false
+            and strpos($Line['text'], ':') === false
+            or strpos($Block['element']['handler']['argument'], "\n") !== false
+        ) {
+            return;
+        }
+
+        if (chop($Line['text'], ' -:|') !== '')
+        {
+            return;
+        }
+
+        $alignments = array();
+
+        $divider = $Line['text'];
+
+        $divider = trim($divider);
+        $divider = trim($divider, '|');
+
+        $dividerCells = explode('|', $divider);
+
+        foreach ($dividerCells as $dividerCell)
+        {
+            $dividerCell = trim($dividerCell);
+
+            if ($dividerCell === '')
+            {
+                return;
+            }
+
+            $alignment = null;
+
+            if ($dividerCell[0] === ':')
+            {
+                $alignment = 'left';
+            }
+
+            if (substr($dividerCell, - 1) === ':')
+            {
+                $alignment = $alignment === 'left' ? 'center' : 'right';
+            }
+
+            $alignments []= $alignment;
+        }
+
+        # ~
+
+        $HeaderElements = array();
+
+        $header = $Block['element']['handler']['argument'];
+
+        $header = trim($header);
+        $header = trim($header, '|');
+
+        $headerCells = explode('|', $header);
+
+        if (count($headerCells) !== count($alignments))
+        {
+            return;
+        }
+
+        foreach ($headerCells as $index => $headerCell)
+        {
+            $headerCell = trim($headerCell);
+
+            $HeaderElement = array(
+                'name' => 'th',
+                'handler' => array(
+                    'function' => 'lineElements',
+                    'argument' => $headerCell,
+                    'destination' => 'elements',
+                )
+            );
+
+            if (isset($alignments[$index]))
+            {
+                $alignment = $alignments[$index];
+
+                $HeaderElement['attributes'] = array(
+                    'style' => "text-align: $alignment;",
+                );
+            }
+
+            $HeaderElements []= $HeaderElement;
+        }
+
+        # ~
+
+        $Block = array(
+            'alignments' => $alignments,
+            'identified' => true,
+            'element' => array(
+                'name' => 'table',
+                'elements' => array(),
+            ),
+        );
+
+        $Block['element']['elements'] []= array(
+            'name' => 'thead',
+        );
+
+        $Block['element']['elements'] []= array(
+            'name' => 'tbody',
+            'elements' => array(),
+        );
+
+        $Block['element']['elements'][0]['elements'] []= array(
+            'name' => 'tr',
+            'elements' => $HeaderElements,
+        );
+
+        return $Block;
+    }
+
+    protected function blockTableContinue($Line, array $Block)
+    {
+        if (isset($Block['interrupted']))
+        {
+            return;
+        }
+
+        if (count($Block['alignments']) === 1 or $Line['text'][0] === '|' or strpos($Line['text'], '|'))
+        {
+            $Elements = array();
+
+            $row = $Line['text'];
+
+            $row = trim($row);
+            $row = trim($row, '|');
+
+            preg_match_all('/(?:(\\\\[|])|[^|`]|`[^`]++`|`)++/', $row, $matches);
+
+            $cells = array_slice($matches[0], 0, count($Block['alignments']));
+
+            foreach ($cells as $index => $cell)
+            {
+                $cell = trim($cell);
+
+                $Element = array(
+                    'name' => 'td',
+                    'handler' => array(
+                        'function' => 'lineElements',
+                        'argument' => $cell,
+                        'destination' => 'elements',
+                    )
+                );
+
+                if (isset($Block['alignments'][$index]))
+                {
+                    $Element['attributes'] = array(
+                        'style' => 'text-align: ' . $Block['alignments'][$index] . ';',
+                    );
+                }
+
+                $Elements []= $Element;
+            }
+
+            $Element = array(
+                'name' => 'tr',
+                'elements' => $Elements,
+            );
+
+            $Block['element']['elements'][1]['elements'] []= $Element;
+
+            return $Block;
+        }
+    }
+
+    #
+    # ~
+    #
+
+    protected function paragraph($Line)
+    {
+        return array(
+            'type' => 'Paragraph',
+            'element' => array(
+                'name' => 'p',
+                'handler' => array(
+                    'function' => 'lineElements',
+                    'argument' => $Line['text'],
+                    'destination' => 'elements',
+                ),
+            ),
+        );
+    }
+
+    protected function paragraphContinue($Line, array $Block)
+    {
+        if (isset($Block['interrupted']))
+        {
+            return;
+        }
+
+        $Block['element']['handler']['argument'] .= "\n".$Line['text'];
+
+        return $Block;
+    }
+
+    #
+    # Inline Elements
+    #
+
+    protected $InlineTypes = array(
+        '!' => array('Image'),
+        '&' => array('SpecialCharacter'),
+        '*' => array('Emphasis'),
+        ':' => array('Url'),
+        '<' => array('UrlTag', 'EmailTag', 'Markup'),
+        '[' => array('Link'),
+        '_' => array('Emphasis'),
+        '`' => array('Code'),
+        '~' => array('Strikethrough'),
+        '\\' => array('EscapeSequence'),
+    );
+
+    # ~
+
+    protected $inlineMarkerList = '!*_&[:<`~\\';
+
+    #
+    # ~
+    #
+
+    public function line($text, $nonNestables = array())
+    {
+        return $this->elements($this->lineElements($text, $nonNestables));
+    }
+
+    protected function lineElements($text, $nonNestables = array())
+    {
+        # standardize line breaks
+        $text = str_replace(array("\r\n", "\r"), "\n", $text);
+
+        $Elements = array();
+
+        $nonNestables = (empty($nonNestables)
+            ? array()
+            : array_combine($nonNestables, $nonNestables)
+        );
+
+        # $excerpt is based on the first occurrence of a marker
+
+        while ($excerpt = strpbrk($text, $this->inlineMarkerList))
+        {
+            $marker = $excerpt[0];
+
+            $markerPosition = strlen($text) - strlen($excerpt);
+
+            $Excerpt = array('text' => $excerpt, 'context' => $text);
+
+            foreach ($this->InlineTypes[$marker] as $inlineType)
+            {
+                # check to see if the current inline type is nestable in the current context
+
+                if (isset($nonNestables[$inlineType]))
+                {
+                    continue;
+                }
+
+                $Inline = $this->{"inline$inlineType"}($Excerpt);
+
+                if ( ! isset($Inline))
+                {
+                    continue;
+                }
+
+                # makes sure that the inline belongs to "our" marker
+
+                if (isset($Inline['position']) and $Inline['position'] > $markerPosition)
+                {
+                    continue;
+                }
+
+                # sets a default inline position
+
+                if ( ! isset($Inline['position']))
+                {
+                    $Inline['position'] = $markerPosition;
+                }
+
+                # cause the new element to 'inherit' our non nestables
+
+
+                $Inline['element']['nonNestables'] = isset($Inline['element']['nonNestables'])
+                    ? array_merge($Inline['element']['nonNestables'], $nonNestables)
+                    : $nonNestables
+                ;
+
+                # the text that comes before the inline
+                $unmarkedText = substr($text, 0, $Inline['position']);
+
+                # compile the unmarked text
+                $InlineText = $this->inlineText($unmarkedText);
+                $Elements[] = $InlineText['element'];
+
+                # compile the inline
+                $Elements[] = $this->extractElement($Inline);
+
+                # remove the examined text
+                $text = substr($text, $Inline['position'] + $Inline['extent']);
+
+                continue 2;
+            }
+
+            # the marker does not belong to an inline
+
+            $unmarkedText = substr($text, 0, $markerPosition + 1);
+
+            $InlineText = $this->inlineText($unmarkedText);
+            $Elements[] = $InlineText['element'];
+
+            $text = substr($text, $markerPosition + 1);
+        }
+
+        $InlineText = $this->inlineText($text);
+        $Elements[] = $InlineText['element'];
+
+        foreach ($Elements as &$Element)
+        {
+            if ( ! isset($Element['autobreak']))
+            {
+                $Element['autobreak'] = false;
+            }
+        }
+
+        return $Elements;
+    }
+
+    #
+    # ~
+    #
+
+    protected function inlineText($text)
+    {
+        $Inline = array(
+            'extent' => strlen($text),
+            'element' => array(),
+        );
+
+        $Inline['element']['elements'] = self::pregReplaceElements(
+            $this->breaksEnabled ? '/[ ]*+\n/' : '/(?:[ ]*+\\\\|[ ]{2,}+)\n/',
+            array(
+                array('name' => 'br'),
+                array('text' => "\n"),
+            ),
+            $text
+        );
+
+        return $Inline;
+    }
+
+    protected function inlineCode($Excerpt)
+    {
+        $marker = $Excerpt['text'][0];
+
+        if (preg_match('/^(['.$marker.']++)[ ]*+(.+?)[ ]*+(? strlen($matches[0]),
+                'element' => array(
+                    'name' => 'code',
+                    'text' => $text,
+                ),
+            );
+        }
+    }
+
+    protected function inlineEmailTag($Excerpt)
+    {
+        $hostnameLabel = '[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?';
+
+        $commonMarkEmail = '[a-zA-Z0-9.!#$%&\'*+\/=?^_`{|}~-]++@'
+            . $hostnameLabel . '(?:\.' . $hostnameLabel . ')*';
+
+        if (strpos($Excerpt['text'], '>') !== false
+            and preg_match("/^<((mailto:)?$commonMarkEmail)>/i", $Excerpt['text'], $matches)
+        ){
+            $url = $matches[1];
+
+            if ( ! isset($matches[2]))
+            {
+                $url = "mailto:$url";
+            }
+
+            return array(
+                'extent' => strlen($matches[0]),
+                'element' => array(
+                    'name' => 'a',
+                    'text' => $matches[1],
+                    'attributes' => array(
+                        'href' => $url,
+                    ),
+                ),
+            );
+        }
+    }
+
+    protected function inlineEmphasis($Excerpt)
+    {
+        if ( ! isset($Excerpt['text'][1]))
+        {
+            return;
+        }
+
+        $marker = $Excerpt['text'][0];
+
+        if ($Excerpt['text'][1] === $marker and preg_match($this->StrongRegex[$marker], $Excerpt['text'], $matches))
+        {
+            $emphasis = 'strong';
+        }
+        elseif (preg_match($this->EmRegex[$marker], $Excerpt['text'], $matches))
+        {
+            $emphasis = 'em';
+        }
+        else
+        {
+            return;
+        }
+
+        return array(
+            'extent' => strlen($matches[0]),
+            'element' => array(
+                'name' => $emphasis,
+                'handler' => array(
+                    'function' => 'lineElements',
+                    'argument' => $matches[1],
+                    'destination' => 'elements',
+                )
+            ),
+        );
+    }
+
+    protected function inlineEscapeSequence($Excerpt)
+    {
+        if (isset($Excerpt['text'][1]) and in_array($Excerpt['text'][1], $this->specialCharacters))
+        {
+            return array(
+                'element' => array('rawHtml' => $Excerpt['text'][1]),
+                'extent' => 2,
+            );
+        }
+    }
+
+    protected function inlineImage($Excerpt)
+    {
+        if ( ! isset($Excerpt['text'][1]) or $Excerpt['text'][1] !== '[')
+        {
+            return;
+        }
+
+        $Excerpt['text']= substr($Excerpt['text'], 1);
+
+        $Link = $this->inlineLink($Excerpt);
+
+        if ($Link === null)
+        {
+            return;
+        }
+
+        $Inline = array(
+            'extent' => $Link['extent'] + 1,
+            'element' => array(
+                'name' => 'img',
+                'attributes' => array(
+                    'src' => $Link['element']['attributes']['href'],
+                    'alt' => $Link['element']['handler']['argument'],
+                ),
+                'autobreak' => true,
+            ),
+        );
+
+        $Inline['element']['attributes'] += $Link['element']['attributes'];
+
+        unset($Inline['element']['attributes']['href']);
+
+        return $Inline;
+    }
+
+    protected function inlineLink($Excerpt)
+    {
+        $Element = array(
+            'name' => 'a',
+            'handler' => array(
+                'function' => 'lineElements',
+                'argument' => null,
+                'destination' => 'elements',
+            ),
+            'nonNestables' => array('Url', 'Link'),
+            'attributes' => array(
+                'href' => null,
+                'title' => null,
+            ),
+        );
+
+        $extent = 0;
+
+        $remainder = $Excerpt['text'];
+
+        if (preg_match('/\[((?:[^][]++|(?R))*+)\]/', $remainder, $matches))
+        {
+            $Element['handler']['argument'] = $matches[1];
+
+            $extent += strlen($matches[0]);
+
+            $remainder = substr($remainder, $extent);
+        }
+        else
+        {
+            return;
+        }
+
+        if (preg_match('/^[(]\s*+((?:[^ ()]++|[(][^ )]+[)])++)(?:[ ]+("[^"]*+"|\'[^\']*+\'))?\s*+[)]/', $remainder, $matches))
+        {
+            $Element['attributes']['href'] = $matches[1];
+
+            if (isset($matches[2]))
+            {
+                $Element['attributes']['title'] = substr($matches[2], 1, - 1);
+            }
+
+            $extent += strlen($matches[0]);
+        }
+        else
+        {
+            if (preg_match('/^\s*\[(.*?)\]/', $remainder, $matches))
+            {
+                $definition = strlen($matches[1]) ? $matches[1] : $Element['handler']['argument'];
+                $definition = strtolower($definition);
+
+                $extent += strlen($matches[0]);
+            }
+            else
+            {
+                $definition = strtolower($Element['handler']['argument']);
+            }
+
+            if ( ! isset($this->DefinitionData['Reference'][$definition]))
+            {
+                return;
+            }
+
+            $Definition = $this->DefinitionData['Reference'][$definition];
+
+            $Element['attributes']['href'] = $Definition['url'];
+            $Element['attributes']['title'] = $Definition['title'];
+        }
+
+        return array(
+            'extent' => $extent,
+            'element' => $Element,
+        );
+    }
+
+    protected function inlineMarkup($Excerpt)
+    {
+        if ($this->markupEscaped or $this->safeMode or strpos($Excerpt['text'], '>') === false)
+        {
+            return;
+        }
+
+        if ($Excerpt['text'][1] === '/' and preg_match('/^<\/\w[\w-]*+[ ]*+>/s', $Excerpt['text'], $matches))
+        {
+            return array(
+                'element' => array('rawHtml' => $matches[0]),
+                'extent' => strlen($matches[0]),
+            );
+        }
+
+        if ($Excerpt['text'][1] === '!' and preg_match('/^/s', $Excerpt['text'], $matches))
+        {
+            return array(
+                'element' => array('rawHtml' => $matches[0]),
+                'extent' => strlen($matches[0]),
+            );
+        }
+
+        if ($Excerpt['text'][1] !== ' ' and preg_match('/^<\w[\w-]*+(?:[ ]*+'.$this->regexHtmlAttribute.')*+[ ]*+\/?>/s', $Excerpt['text'], $matches))
+        {
+            return array(
+                'element' => array('rawHtml' => $matches[0]),
+                'extent' => strlen($matches[0]),
+            );
+        }
+    }
+
+    protected function inlineSpecialCharacter($Excerpt)
+    {
+        if (substr($Excerpt['text'], 1, 1) !== ' ' and strpos($Excerpt['text'], ';') !== false
+            and preg_match('/^&(#?+[0-9a-zA-Z]++);/', $Excerpt['text'], $matches)
+        ) {
+            return array(
+                'element' => array('rawHtml' => '&' . $matches[1] . ';'),
+                'extent' => strlen($matches[0]),
+            );
+        }
+
+        return;
+    }
+
+    protected function inlineStrikethrough($Excerpt)
+    {
+        if ( ! isset($Excerpt['text'][1]))
+        {
+            return;
+        }
+
+        if ($Excerpt['text'][1] === '~' and preg_match('/^~~(?=\S)(.+?)(?<=\S)~~/', $Excerpt['text'], $matches))
+        {
+            return array(
+                'extent' => strlen($matches[0]),
+                'element' => array(
+                    'name' => 'del',
+                    'handler' => array(
+                        'function' => 'lineElements',
+                        'argument' => $matches[1],
+                        'destination' => 'elements',
+                    )
+                ),
+            );
+        }
+    }
+
+    protected function inlineUrl($Excerpt)
+    {
+        if ($this->urlsLinked !== true or ! isset($Excerpt['text'][2]) or $Excerpt['text'][2] !== '/')
+        {
+            return;
+        }
+
+        if (strpos($Excerpt['context'], 'http') !== false
+            and preg_match('/\bhttps?+:[\/]{2}[^\s<]+\b\/*+/ui', $Excerpt['context'], $matches, PREG_OFFSET_CAPTURE)
+        ) {
+            $url = $matches[0][0];
+
+            $Inline = array(
+                'extent' => strlen($matches[0][0]),
+                'position' => $matches[0][1],
+                'element' => array(
+                    'name' => 'a',
+                    'text' => $url,
+                    'attributes' => array(
+                        'href' => $url,
+                    ),
+                ),
+            );
+
+            return $Inline;
+        }
+    }
+
+    protected function inlineUrlTag($Excerpt)
+    {
+        if (strpos($Excerpt['text'], '>') !== false and preg_match('/^<(\w++:\/{2}[^ >]++)>/i', $Excerpt['text'], $matches))
+        {
+            $url = $matches[1];
+
+            return array(
+                'extent' => strlen($matches[0]),
+                'element' => array(
+                    'name' => 'a',
+                    'text' => $url,
+                    'attributes' => array(
+                        'href' => $url,
+                    ),
+                ),
+            );
+        }
+    }
+
+    # ~
+
+    protected function unmarkedText($text)
+    {
+        $Inline = $this->inlineText($text);
+        return $this->element($Inline['element']);
+    }
+
+    #
+    # Handlers
+    #
+
+    protected function handle(array $Element)
+    {
+        if (isset($Element['handler']))
+        {
+            if (!isset($Element['nonNestables']))
+            {
+                $Element['nonNestables'] = array();
+            }
+
+            if (is_string($Element['handler']))
+            {
+                $function = $Element['handler'];
+                $argument = $Element['text'];
+                unset($Element['text']);
+                $destination = 'rawHtml';
+            }
+            else
+            {
+                $function = $Element['handler']['function'];
+                $argument = $Element['handler']['argument'];
+                $destination = $Element['handler']['destination'];
+            }
+
+            $Element[$destination] = $this->{$function}($argument, $Element['nonNestables']);
+
+            if ($destination === 'handler')
+            {
+                $Element = $this->handle($Element);
+            }
+
+            unset($Element['handler']);
+        }
+
+        return $Element;
+    }
+
+    protected function handleElementRecursive(array $Element)
+    {
+        return $this->elementApplyRecursive(array($this, 'handle'), $Element);
+    }
+
+    protected function handleElementsRecursive(array $Elements)
+    {
+        return $this->elementsApplyRecursive(array($this, 'handle'), $Elements);
+    }
+
+    protected function elementApplyRecursive($closure, array $Element)
+    {
+        $Element = call_user_func($closure, $Element);
+
+        if (isset($Element['elements']))
+        {
+            $Element['elements'] = $this->elementsApplyRecursive($closure, $Element['elements']);
+        }
+        elseif (isset($Element['element']))
+        {
+            $Element['element'] = $this->elementApplyRecursive($closure, $Element['element']);
+        }
+
+        return $Element;
+    }
+
+    protected function elementApplyRecursiveDepthFirst($closure, array $Element)
+    {
+        if (isset($Element['elements']))
+        {
+            $Element['elements'] = $this->elementsApplyRecursiveDepthFirst($closure, $Element['elements']);
+        }
+        elseif (isset($Element['element']))
+        {
+            $Element['element'] = $this->elementsApplyRecursiveDepthFirst($closure, $Element['element']);
+        }
+
+        $Element = call_user_func($closure, $Element);
+
+        return $Element;
+    }
+
+    protected function elementsApplyRecursive($closure, array $Elements)
+    {
+        foreach ($Elements as &$Element)
+        {
+            $Element = $this->elementApplyRecursive($closure, $Element);
+        }
+
+        return $Elements;
+    }
+
+    protected function elementsApplyRecursiveDepthFirst($closure, array $Elements)
+    {
+        foreach ($Elements as &$Element)
+        {
+            $Element = $this->elementApplyRecursiveDepthFirst($closure, $Element);
+        }
+
+        return $Elements;
+    }
+
+    protected function element(array $Element)
+    {
+        if ($this->safeMode)
+        {
+            $Element = $this->sanitiseElement($Element);
+        }
+
+        # identity map if element has no handler
+        $Element = $this->handle($Element);
+
+        $hasName = isset($Element['name']);
+
+        $markup = '';
+
+        if ($hasName)
+        {
+            $markup .= '<' . $Element['name'];
+
+            if (isset($Element['attributes']))
+            {
+                foreach ($Element['attributes'] as $name => $value)
+                {
+                    if ($value === null)
+                    {
+                        continue;
+                    }
+
+                    $markup .= " $name=\"".self::escape($value).'"';
+                }
+            }
+        }
+
+        $permitRawHtml = false;
+
+        if (isset($Element['text']))
+        {
+            $text = $Element['text'];
+        }
+        // very strongly consider an alternative if you're writing an
+        // extension
+        elseif (isset($Element['rawHtml']))
+        {
+            $text = $Element['rawHtml'];
+
+            $allowRawHtmlInSafeMode = isset($Element['allowRawHtmlInSafeMode']) && $Element['allowRawHtmlInSafeMode'];
+            $permitRawHtml = !$this->safeMode || $allowRawHtmlInSafeMode;
+        }
+
+        $hasContent = isset($text) || isset($Element['element']) || isset($Element['elements']);
+
+        if ($hasContent)
+        {
+            $markup .= $hasName ? '>' : '';
+
+            if (isset($Element['elements']))
+            {
+                $markup .= $this->elements($Element['elements']);
+            }
+            elseif (isset($Element['element']))
+            {
+                $markup .= $this->element($Element['element']);
+            }
+            else
+            {
+                if (!$permitRawHtml)
+                {
+                    $markup .= self::escape($text, true);
+                }
+                else
+                {
+                    $markup .= $text;
+                }
+            }
+
+            $markup .= $hasName ? '' : '';
+        }
+        elseif ($hasName)
+        {
+            $markup .= ' />';
+        }
+
+        return $markup;
+    }
+
+    protected function elements(array $Elements)
+    {
+        $markup = '';
+
+        $autoBreak = true;
+
+        foreach ($Elements as $Element)
+        {
+            if (empty($Element))
+            {
+                continue;
+            }
+
+            $autoBreakNext = (isset($Element['autobreak'])
+                ? $Element['autobreak'] : isset($Element['name'])
+            );
+            // (autobreak === false) covers both sides of an element
+            $autoBreak = !$autoBreak ? $autoBreak : $autoBreakNext;
+
+            $markup .= ($autoBreak ? "\n" : '') . $this->element($Element);
+            $autoBreak = $autoBreakNext;
+        }
+
+        $markup .= $autoBreak ? "\n" : '';
+
+        return $markup;
+    }
+
+    # ~
+
+    protected function li($lines)
+    {
+        $Elements = $this->linesElements($lines);
+
+        if ( ! in_array('', $lines)
+            and isset($Elements[0]) and isset($Elements[0]['name'])
+            and $Elements[0]['name'] === 'p'
+        ) {
+            unset($Elements[0]['name']);
+        }
+
+        return $Elements;
+    }
+
+    #
+    # AST Convenience
+    #
+
+    /**
+     * Replace occurrences $regexp with $Elements in $text. Return an array of
+     * elements representing the replacement.
+     */
+    protected static function pregReplaceElements($regexp, $Elements, $text)
+    {
+        $newElements = array();
+
+        while (preg_match($regexp, $text, $matches, PREG_OFFSET_CAPTURE))
+        {
+            $offset = $matches[0][1];
+            $before = substr($text, 0, $offset);
+            $after = substr($text, $offset + strlen($matches[0][0]));
+
+            $newElements[] = array('text' => $before);
+
+            foreach ($Elements as $Element)
+            {
+                $newElements[] = $Element;
+            }
+
+            $text = $after;
+        }
+
+        $newElements[] = array('text' => $text);
+
+        return $newElements;
+    }
+
+    #
+    # Deprecated Methods
+    #
+
+    function parse($text)
+    {
+        $markup = $this->text($text);
+
+        return $markup;
+    }
+
+    protected function sanitiseElement(array $Element)
+    {
+        static $goodAttribute = '/^[a-zA-Z0-9][a-zA-Z0-9-_]*+$/';
+        static $safeUrlNameToAtt  = array(
+            'a'   => 'href',
+            'img' => 'src',
+        );
+
+        if ( ! isset($Element['name']))
+        {
+            unset($Element['attributes']);
+            return $Element;
+        }
+
+        if (isset($safeUrlNameToAtt[$Element['name']]))
+        {
+            $Element = $this->filterUnsafeUrlInAttribute($Element, $safeUrlNameToAtt[$Element['name']]);
+        }
+
+        if ( ! empty($Element['attributes']))
+        {
+            foreach ($Element['attributes'] as $att => $val)
+            {
+                # filter out badly parsed attribute
+                if ( ! preg_match($goodAttribute, $att))
+                {
+                    unset($Element['attributes'][$att]);
+                }
+                # dump onevent attribute
+                elseif (self::striAtStart($att, 'on'))
+                {
+                    unset($Element['attributes'][$att]);
+                }
+            }
+        }
+
+        return $Element;
+    }
+
+    protected function filterUnsafeUrlInAttribute(array $Element, $attribute)
+    {
+        foreach ($this->safeLinksWhitelist as $scheme)
+        {
+            if (self::striAtStart($Element['attributes'][$attribute], $scheme))
+            {
+                return $Element;
+            }
+        }
+
+        $Element['attributes'][$attribute] = str_replace(':', '%3A', $Element['attributes'][$attribute]);
+
+        return $Element;
+    }
+
+    #
+    # Static Methods
+    #
+
+    protected static function escape($text, $allowQuotes = false)
+    {
+        return htmlspecialchars($text, $allowQuotes ? ENT_NOQUOTES : ENT_QUOTES, 'UTF-8');
+    }
+
+    protected static function striAtStart($string, $needle)
+    {
+        $len = strlen($needle);
+
+        if ($len > strlen($string))
+        {
+            return false;
+        }
+        else
+        {
+            return strtolower(substr($string, 0, $len)) === strtolower($needle);
+        }
+    }
+
+    static function instance($name = 'default')
+    {
+        if (isset(self::$instances[$name]))
+        {
+            return self::$instances[$name];
+        }
+
+        $instance = new static();
+
+        self::$instances[$name] = $instance;
+
+        return $instance;
+    }
+
+    private static $instances = array();
+
+    #
+    # Fields
+    #
+
+    protected $DefinitionData;
+
+    #
+    # Read-Only
+
+    protected $specialCharacters = array(
+        '\\', '`', '*', '_', '{', '}', '[', ']', '(', ')', '>', '#', '+', '-', '.', '!', '|', '~'
+    );
+
+    protected $StrongRegex = array(
+        '*' => '/^[*]{2}((?:\\\\\*|[^*]|[*][^*]*+[*])+?)[*]{2}(?![*])/s',
+        '_' => '/^__((?:\\\\_|[^_]|_[^_]*+_)+?)__(?!_)/us',
+    );
+
+    protected $EmRegex = array(
+        '*' => '/^[*]((?:\\\\\*|[^*]|[*][*][^*]+?[*][*])+?)[*](?![*])/s',
+        '_' => '/^_((?:\\\\_|[^_]|__[^_]*__)+?)_(?!_)\b/us',
+    );
+
+    protected $regexHtmlAttribute = '[a-zA-Z_:][\w:.-]*+(?:\s*+=\s*+(?:[^"\'=<>`\s]+|"[^"]*+"|\'[^\']*+\'))?+';
+
+    protected $voidElements = array(
+        'area', 'base', 'br', 'col', 'command', 'embed', 'hr', 'img', 'input', 'link', 'meta', 'param', 'source',
+    );
+
+    protected $textLevelElements = array(
+        'a', 'br', 'bdo', 'abbr', 'blink', 'nextid', 'acronym', 'basefont',
+        'b', 'em', 'big', 'cite', 'small', 'spacer', 'listing',
+        'i', 'rp', 'del', 'code',          'strike', 'marquee',
+        'q', 'rt', 'ins', 'font',          'strong',
+        's', 'tt', 'kbd', 'mark',
+        'u', 'xm', 'sub', 'nobr',
+                   'sup', 'ruby',
+                   'var', 'span',
+                   'wbr', 'time',
+    );
+}
diff --git a/lib/parsedownextraplugin/parsedownextra.php b/lib/parsedownextraplugin/parsedownextra.php
new file mode 100644
index 0000000000..2eeeda6e0b
--- /dev/null
+++ b/lib/parsedownextraplugin/parsedownextra.php
@@ -0,0 +1,686 @@
+BlockTypes[':'] []= 'DefinitionList';
+        $this->BlockTypes['*'] []= 'Abbreviation';
+
+        # identify footnote definitions before reference definitions
+        array_unshift($this->BlockTypes['['], 'Footnote');
+
+        # identify footnote markers before before links
+        array_unshift($this->InlineTypes['['], 'FootnoteMarker');
+    }
+
+    #
+    # ~
+
+    function text($text)
+    {
+        $Elements = $this->textElements($text);
+
+        # convert to markup
+        $markup = $this->elements($Elements);
+
+        # trim line breaks
+        $markup = trim($markup, "\n");
+
+        # merge consecutive dl elements
+
+        $markup = preg_replace('/<\/dl>\s+
    \s+/', '', $markup);
+
+        # add footnotes
+
+        if (isset($this->DefinitionData['Footnote']))
+        {
+            $Element = $this->buildFootnoteElement();
+
+            $markup .= "\n" . $this->element($Element);
+        }
+
+        return $markup;
+    }
+
+    #
+    # Blocks
+    #
+
+    #
+    # Abbreviation
+
+    protected function blockAbbreviation($Line)
+    {
+        if (preg_match('/^\*\[(.+?)\]:[ ]*(.+?)[ ]*$/', $Line['text'], $matches))
+        {
+            $this->DefinitionData['Abbreviation'][$matches[1]] = $matches[2];
+
+            $Block = array(
+                'hidden' => true,
+            );
+
+            return $Block;
+        }
+    }
+
+    #
+    # Footnote
+
+    protected function blockFootnote($Line)
+    {
+        if (preg_match('/^\[\^(.+?)\]:[ ]?(.*)$/', $Line['text'], $matches))
+        {
+            $Block = array(
+                'label' => $matches[1],
+                'text' => $matches[2],
+                'hidden' => true,
+            );
+
+            return $Block;
+        }
+    }
+
+    protected function blockFootnoteContinue($Line, $Block)
+    {
+        if ($Line['text'][0] === '[' and preg_match('/^\[\^(.+?)\]:/', $Line['text']))
+        {
+            return;
+        }
+
+        if (isset($Block['interrupted']))
+        {
+            if ($Line['indent'] >= 4)
+            {
+                $Block['text'] .= "\n\n" . $Line['text'];
+
+                return $Block;
+            }
+        }
+        else
+        {
+            $Block['text'] .= "\n" . $Line['text'];
+
+            return $Block;
+        }
+    }
+
+    protected function blockFootnoteComplete($Block)
+    {
+        $this->DefinitionData['Footnote'][$Block['label']] = array(
+            'text' => $Block['text'],
+            'count' => null,
+            'number' => null,
+        );
+
+        return $Block;
+    }
+
+    #
+    # Definition List
+
+    protected function blockDefinitionList($Line, $Block)
+    {
+        if ( ! isset($Block) or $Block['type'] !== 'Paragraph')
+        {
+            return;
+        }
+
+        $Element = array(
+            'name' => 'dl',
+            'elements' => array(),
+        );
+
+        $terms = explode("\n", $Block['element']['handler']['argument']);
+
+        foreach ($terms as $term)
+        {
+            $Element['elements'] []= array(
+                'name' => 'dt',
+                'handler' => array(
+                    'function' => 'lineElements',
+                    'argument' => $term,
+                    'destination' => 'elements'
+                ),
+            );
+        }
+
+        $Block['element'] = $Element;
+
+        $Block = $this->addDdElement($Line, $Block);
+
+        return $Block;
+    }
+
+    protected function blockDefinitionListContinue($Line, array $Block)
+    {
+        if ($Line['text'][0] === ':')
+        {
+            $Block = $this->addDdElement($Line, $Block);
+
+            return $Block;
+        }
+        else
+        {
+            if (isset($Block['interrupted']) and $Line['indent'] === 0)
+            {
+                return;
+            }
+
+            if (isset($Block['interrupted']))
+            {
+                $Block['dd']['handler']['function'] = 'textElements';
+                $Block['dd']['handler']['argument'] .= "\n\n";
+
+                $Block['dd']['handler']['destination'] = 'elements';
+
+                unset($Block['interrupted']);
+            }
+
+            $text = substr($Line['body'], min($Line['indent'], 4));
+
+            $Block['dd']['handler']['argument'] .= "\n" . $text;
+
+            return $Block;
+        }
+    }
+
+    #
+    # Header
+
+    protected function blockHeader($Line)
+    {
+        $Block = parent::blockHeader($Line);
+
+        if ($Block !== null && preg_match('/[ #]*{('.$this->regexAttribute.'+)}[ ]*$/', $Block['element']['handler']['argument'], $matches, PREG_OFFSET_CAPTURE))
+        {
+            $attributeString = $matches[1][0];
+
+            $Block['element']['attributes'] = $this->parseAttributeData($attributeString);
+
+            $Block['element']['handler']['argument'] = substr($Block['element']['handler']['argument'], 0, $matches[0][1]);
+        }
+
+        return $Block;
+    }
+
+    #
+    # Markup
+
+    protected function blockMarkup($Line)
+    {
+        if ($this->markupEscaped or $this->safeMode)
+        {
+            return;
+        }
+
+        if (preg_match('/^<(\w[\w-]*)(?:[ ]*'.$this->regexHtmlAttribute.')*[ ]*(\/)?>/', $Line['text'], $matches))
+        {
+            $element = strtolower($matches[1]);
+
+            if (in_array($element, $this->textLevelElements))
+            {
+                return;
+            }
+
+            $Block = array(
+                'name' => $matches[1],
+                'depth' => 0,
+                'element' => array(
+                    'rawHtml' => $Line['text'],
+                    'autobreak' => true,
+                ),
+            );
+
+            $length = strlen($matches[0]);
+            $remainder = substr($Line['text'], $length);
+
+            if (trim($remainder) === '')
+            {
+                if (isset($matches[2]) or in_array($matches[1], $this->voidElements))
+                {
+                    $Block['closed'] = true;
+                    $Block['void'] = true;
+                }
+            }
+            else
+            {
+                if (isset($matches[2]) or in_array($matches[1], $this->voidElements))
+                {
+                    return;
+                }
+                if (preg_match('/<\/'.$matches[1].'>[ ]*$/i', $remainder))
+                {
+                    $Block['closed'] = true;
+                }
+            }
+
+            return $Block;
+        }
+    }
+
+    protected function blockMarkupContinue($Line, array $Block)
+    {
+        if (isset($Block['closed']))
+        {
+            return;
+        }
+
+        if (preg_match('/^<'.$Block['name'].'(?:[ ]*'.$this->regexHtmlAttribute.')*[ ]*>/i', $Line['text'])) # open
+        {
+            $Block['depth'] ++;
+        }
+
+        if (preg_match('/(.*?)<\/'.$Block['name'].'>[ ]*$/i', $Line['text'], $matches)) # close
+        {
+            if ($Block['depth'] > 0)
+            {
+                $Block['depth'] --;
+            }
+            else
+            {
+                $Block['closed'] = true;
+            }
+        }
+
+        if (isset($Block['interrupted']))
+        {
+            $Block['element']['rawHtml'] .= "\n";
+            unset($Block['interrupted']);
+        }
+
+        $Block['element']['rawHtml'] .= "\n".$Line['body'];
+
+        return $Block;
+    }
+
+    protected function blockMarkupComplete($Block)
+    {
+        if ( ! isset($Block['void']))
+        {
+            $Block['element']['rawHtml'] = $this->processTag($Block['element']['rawHtml']);
+        }
+
+        return $Block;
+    }
+
+    #
+    # Setext
+
+    protected function blockSetextHeader($Line, array $Block = null)
+    {
+        $Block = parent::blockSetextHeader($Line, $Block);
+
+        if ($Block !== null && preg_match('/[ ]*{('.$this->regexAttribute.'+)}[ ]*$/', $Block['element']['handler']['argument'], $matches, PREG_OFFSET_CAPTURE))
+        {
+            $attributeString = $matches[1][0];
+
+            $Block['element']['attributes'] = $this->parseAttributeData($attributeString);
+
+            $Block['element']['handler']['argument'] = substr($Block['element']['handler']['argument'], 0, $matches[0][1]);
+        }
+
+        return $Block;
+    }
+
+    #
+    # Inline Elements
+    #
+
+    #
+    # Footnote Marker
+
+    protected function inlineFootnoteMarker($Excerpt)
+    {
+        if (preg_match('/^\[\^(.+?)\]/', $Excerpt['text'], $matches))
+        {
+            $name = $matches[1];
+
+            if ( ! isset($this->DefinitionData['Footnote'][$name]))
+            {
+                return;
+            }
+
+            $this->DefinitionData['Footnote'][$name]['count'] ++;
+
+            if ( ! isset($this->DefinitionData['Footnote'][$name]['number']))
+            {
+                $this->DefinitionData['Footnote'][$name]['number'] = ++ $this->footnoteCount; # » &
+            }
+
+            $Element = array(
+                'name' => 'sup',
+                'attributes' => array('id' => 'fnref'.$this->DefinitionData['Footnote'][$name]['count'].':'.$name),
+                'element' => array(
+                    'name' => 'a',
+                    'attributes' => array('href' => '#fn:'.$name, 'class' => 'footnote-ref'),
+                    'text' => $this->DefinitionData['Footnote'][$name]['number'],
+                ),
+            );
+
+            return array(
+                'extent' => strlen($matches[0]),
+                'element' => $Element,
+            );
+        }
+    }
+
+    private $footnoteCount = 0;
+
+    #
+    # Link
+
+    protected function inlineLink($Excerpt)
+    {
+        $Link = parent::inlineLink($Excerpt);
+
+        $remainder = $Link !== null ? substr($Excerpt['text'], $Link['extent']) : '';
+
+        if (preg_match('/^[ ]*{('.$this->regexAttribute.'+)}/', $remainder, $matches))
+        {
+            $Link['element']['attributes'] += $this->parseAttributeData($matches[1]);
+
+            $Link['extent'] += strlen($matches[0]);
+        }
+
+        return $Link;
+    }
+
+    #
+    # ~
+    #
+
+    private $currentAbreviation;
+    private $currentMeaning;
+
+    protected function insertAbreviation(array $Element)
+    {
+        if (isset($Element['text']))
+        {
+            $Element['elements'] = self::pregReplaceElements(
+                '/\b'.preg_quote($this->currentAbreviation, '/').'\b/',
+                array(
+                    array(
+                        'name' => 'abbr',
+                        'attributes' => array(
+                            'title' => $this->currentMeaning,
+                        ),
+                        'text' => $this->currentAbreviation,
+                    )
+                ),
+                $Element['text']
+            );
+
+            unset($Element['text']);
+        }
+
+        return $Element;
+    }
+
+    protected function inlineText($text)
+    {
+        $Inline = parent::inlineText($text);
+
+        if (isset($this->DefinitionData['Abbreviation']))
+        {
+            foreach ($this->DefinitionData['Abbreviation'] as $abbreviation => $meaning)
+            {
+                $this->currentAbreviation = $abbreviation;
+                $this->currentMeaning = $meaning;
+
+                $Inline['element'] = $this->elementApplyRecursiveDepthFirst(
+                    array($this, 'insertAbreviation'),
+                    $Inline['element']
+                );
+            }
+        }
+
+        return $Inline;
+    }
+
+    #
+    # Util Methods
+    #
+
+    protected function addDdElement(array $Line, array $Block)
+    {
+        $text = substr($Line['text'], 1);
+        $text = trim($text);
+
+        unset($Block['dd']);
+
+        $Block['dd'] = array(
+            'name' => 'dd',
+            'handler' => array(
+                'function' => 'lineElements',
+                'argument' => $text,
+                'destination' => 'elements'
+            ),
+        );
+
+        if (isset($Block['interrupted']))
+        {
+            $Block['dd']['handler']['function'] = 'textElements';
+
+            unset($Block['interrupted']);
+        }
+
+        $Block['element']['elements'] []= & $Block['dd'];
+
+        return $Block;
+    }
+
+    protected function buildFootnoteElement()
+    {
+        $Element = array(
+            'name' => 'div',
+            'attributes' => array('class' => 'footnotes'),
+            'elements' => array(
+                array('name' => 'hr'),
+                array(
+                    'name' => 'ol',
+                    'elements' => array(),
+                ),
+            ),
+        );
+
+        uasort($this->DefinitionData['Footnote'], 'self::sortFootnotes');
+
+        foreach ($this->DefinitionData['Footnote'] as $definitionId => $DefinitionData)
+        {
+            if ( ! isset($DefinitionData['number']))
+            {
+                continue;
+            }
+
+            $text = $DefinitionData['text'];
+
+            $textElements = parent::textElements($text);
+
+            $numbers = range(1, $DefinitionData['count']);
+
+            $backLinkElements = array();
+
+            foreach ($numbers as $number)
+            {
+                $backLinkElements[] = array('text' => ' ');
+                $backLinkElements[] = array(
+                    'name' => 'a',
+                    'attributes' => array(
+                        'href' => "#fnref$number:$definitionId",
+                        'rev' => 'footnote',
+                        'class' => 'footnote-backref',
+                    ),
+                    'rawHtml' => '↩',
+                    'allowRawHtmlInSafeMode' => true,
+                    'autobreak' => false,
+                );
+            }
+
+            unset($backLinkElements[0]);
+
+            $n = count($textElements) -1;
+
+            if ($textElements[$n]['name'] === 'p')
+            {
+                $backLinkElements = array_merge(
+                    array(
+                        array(
+                            'rawHtml' => ' ',
+                            'allowRawHtmlInSafeMode' => true,
+                        ),
+                    ),
+                    $backLinkElements
+                );
+
+                unset($textElements[$n]['name']);
+
+                $textElements[$n] = array(
+                    'name' => 'p',
+                    'elements' => array_merge(
+                        array($textElements[$n]),
+                        $backLinkElements
+                    ),
+                );
+            }
+            else
+            {
+                $textElements[] = array(
+                    'name' => 'p',
+                    'elements' => $backLinkElements
+                );
+            }
+
+            $Element['elements'][1]['elements'] []= array(
+                'name' => 'li',
+                'attributes' => array('id' => 'fn:'.$definitionId),
+                'elements' => array_merge(
+                    $textElements
+                ),
+            );
+        }
+
+        return $Element;
+    }
+
+    # ~
+
+    protected function parseAttributeData($attributeString)
+    {
+        $Data = array();
+
+        $attributes = preg_split('/[ ]+/', $attributeString, - 1, PREG_SPLIT_NO_EMPTY);
+
+        foreach ($attributes as $attribute)
+        {
+            if ($attribute[0] === '#')
+            {
+                $Data['id'] = substr($attribute, 1);
+            }
+            else # "."
+            {
+                $classes []= substr($attribute, 1);
+            }
+        }
+
+        if (isset($classes))
+        {
+            $Data['class'] = implode(' ', $classes);
+        }
+
+        return $Data;
+    }
+
+    # ~
+
+    protected function processTag($elementMarkup) # recursive
+    {
+        # http://stackoverflow.com/q/1148928/200145
+        libxml_use_internal_errors(true);
+
+        $DOMDocument = new DOMDocument;
+
+        # http://stackoverflow.com/q/11309194/200145
+        $elementMarkup = mb_convert_encoding($elementMarkup, 'HTML-ENTITIES', 'UTF-8');
+
+        # http://stackoverflow.com/q/4879946/200145
+        $DOMDocument->loadHTML($elementMarkup);
+        $DOMDocument->removeChild($DOMDocument->doctype);
+        $DOMDocument->replaceChild($DOMDocument->firstChild->firstChild->firstChild, $DOMDocument->firstChild);
+
+        $elementText = '';
+
+        if ($DOMDocument->documentElement->getAttribute('markdown') === '1')
+        {
+            foreach ($DOMDocument->documentElement->childNodes as $Node)
+            {
+                $elementText .= $DOMDocument->saveHTML($Node);
+            }
+
+            $DOMDocument->documentElement->removeAttribute('markdown');
+
+            $elementText = "\n".$this->text($elementText)."\n";
+        }
+        else
+        {
+            foreach ($DOMDocument->documentElement->childNodes as $Node)
+            {
+                $nodeMarkup = $DOMDocument->saveHTML($Node);
+
+                if ($Node instanceof DOMElement and ! in_array($Node->nodeName, $this->textLevelElements))
+                {
+                    $elementText .= $this->processTag($nodeMarkup);
+                }
+                else
+                {
+                    $elementText .= $nodeMarkup;
+                }
+            }
+        }
+
+        # because we don't want for markup to get encoded
+        $DOMDocument->documentElement->nodeValue = 'placeholder\x1A';
+
+        $markup = $DOMDocument->saveHTML($DOMDocument->documentElement);
+        $markup = str_replace('placeholder\x1A', $elementText, $markup);
+
+        return $markup;
+    }
+
+    # ~
+
+    protected function sortFootnotes($A, $B) # callback
+    {
+        return $A['number'] - $B['number'];
+    }
+
+    #
+    # Fields
+    #
+
+    protected $regexAttribute = '(?:[#.][-\w]+[ ]*)';
+}
diff --git a/lib/parsedownextraplugin/parsedownextraplugin.class.php b/lib/parsedownextraplugin/parsedownextraplugin.class.php
new file mode 100644
index 0000000000..f4787db640
--- /dev/null
+++ b/lib/parsedownextraplugin/parsedownextraplugin.class.php
@@ -0,0 +1,590 @@
+';
+
+    protected $regexAttribute = '(?:[#.][-\w:\\\]+[ ]*|[-\w:\\\]+(?:=(?:["\'][^\n]*?["\']|[^\s]+)?)?[ ]*)';
+
+    # Method aliases for every configuration property
+    public function __call($key, array $arguments = array()) {
+        $property = lcfirst(substr($key, 3));
+        if (strpos($key, 'set') === 0 && property_exists($this, $property)) {
+            $this->{$property} = $arguments[0];
+            return $this;
+        }
+        throw new Exception('Method ' . $key . ' does not exists.');
+    }
+
+    public function __construct() {
+        if (version_compare(parent::version, '0.8.0-beta-1') < 0) {
+            throw new Exception('ParsedownExtraPlugin requires a later version of Parsedown');
+        }
+        $this->BlockTypes['!'][] = 'Image';
+        parent::__construct();
+    }
+
+    protected function blockAbbreviation($Line) {
+        // Allow empty abbreviations
+        if (preg_match('/^\*\[(.+?)\]:[ ]*$/', $Line['text'], $matches)) {
+            $this->DefinitionData['Abbreviation'][$matches[1]] = null;
+            return array('hidden' => true);
+        }
+        return parent::blockAbbreviation($Line);
+    }
+
+    protected function blockCodeComplete($Block) {
+        $this->doSetAttributes($Block['element']['element'], $this->blockCodeAttributes);
+        $this->doSetContent($Block['element']['element'], $this->blockCodeHtml, true);
+        // Put code attributes on parent element
+        if ($this->codeAttributesOnParent) {
+            if ($this->codeAttributesOnParent === true) {
+                // $this->codeAttributesOnParent = array_keys($Block['element']['element']['attributes']);
+                $this->codeAttributesOnParent = array('class', 'id');
+            }
+            foreach ((array) $this->codeAttributesOnParent as $Name) {
+                if (isset($Block['element']['element']['attributes'][$Name])) {
+                    $Block['element']['attributes'][$Name] = $Block['element']['element']['attributes'][$Name];
+                    unset($Block['element']['element']['attributes'][$Name]);
+                }
+            }
+        }
+        $Block['element']['element']['rawHtml'] = $Block['element']['element']['text'];
+        $Block['element']['element']['allowRawHtmlInSafeMode'] = true;
+        unset($Block['element']['element']['text']);
+        return $Block;
+    }
+
+    protected function blockFencedCode($Line) {
+        // Re-enable the multiple class name feature
+        $Line['text'] = strtr(trim($Line['text']), array(
+            ' ' => "\x1A",
+            '.' => "\x1A."
+        ));
+        // Enable custom attribute syntax on code block
+        $Attributes = array();
+        if (strpos($Line['text'], '{') !== false && substr($Line['text'], -1) === '}') {
+            $Parts = explode('{', $Line['text'], 2);
+            $Attributes = $this->parseAttributeData(strtr(substr($Parts[1], 0, -1), "\x1A", ' '));
+            $Line['text'] = trim($Parts[0]);
+        }
+        if (!$Block = parent::blockFencedCode($Line)) {
+            return;
+        }
+        if ($Attributes) {
+            $Block['element']['element']['attributes'] = $Attributes;
+        } else if (isset($Block['element']['element']['attributes']['class'])) {
+            $Classes = explode("\x1A", strtr($Block['element']['element']['attributes']['class'], ' ', "\x1A"));
+            // `~~~ php` → `
    `
+            // `~~~ php html` → `
    `
+            // `~~~ .php` → `
    `
+            // `~~~ .php.html` → `
    `
+            // `~~~ .php html` → `
    `
+            // `~~~ {.php #foo}` → `
    `
+            $Results = [];
+            foreach ($Classes as $Class) {
+                if ($Class === "" || $Class === strtr($this->blockCodeClassFormat, array('%s' => ""))) {
+                    continue;
+                }
+                if ($Class[0] === '.') {
+                    $Results[] = substr($Class, 1);
+                } else if (preg_match('/^' . strtr(preg_quote($this->blockCodeClassFormat), array('%s' => '\S+')) . '$/', $Class)) {
+                    $Results[] = $Class; // Do nothing!
+                } else {
+                    $Results[] = sprintf($this->blockCodeClassFormat, $Class);
+                }
+            }
+            if ($Results = array_unique($Results)) {
+                $Block['element']['element']['attributes']['class'] = implode(' ', $Results);
+            } else {
+                unset($Block['element']['element']['attributes']['class']);
+            }
+        }
+        return $Block;
+    }
+
+    protected function blockFencedCodeComplete($Block) {
+        return $this->blockCodeComplete($Block);
+    }
+
+    protected function blockHeader($Line) {
+        if (!$Block = parent::blockHeader($Line)) {
+            return;
+        }
+        $Level = strspn($Line['text'], '#');
+        $this->doSetAttributes($Block['element'], $this->headerAttributes, array($Level));
+        $this->doSetContent($Block['element'], $this->headerText, false, 'argument', array($Level));
+        return $Block;
+    }
+
+    protected function blockImage($Line) {
+        if (!$this->figuresEnabled) {
+            return;
+        }
+        // Match exactly an image syntax in a paragraph (with optional custom attributes, and optional hard break marker)
+        if (preg_match('/^\!\[[^\n]*?\](\[[^\n]*?\]|\([^\n]*?\))(\s*\{' . $this->regexAttribute . '+?\})?([ ]{2})?$/', $Line['text'])) {
+            $Block = array(
+                'description' => "",
+                'element' => array(
+                    'name' => 'figure',
+                    'attributes' => array(),
+                    'elements' => array(
+                        $this->inlineImage($Line)
+                    )
+                )
+            );
+            $this->doSetAttributes($Block['element'], $this->figureAttributes);
+            return $Block;
+        }
+        return;
+    }
+
+    protected function blockImageComplete($Block) {
+        if (!empty($Block['description'])) {
+            $Description = $Block['description'];
+            $Block['element']['elements'][] = array(
+                'name' => 'figcaption',
+                'rawHtml' => $this->{strpos($Description, "\n\n") === false ? 'line' : 'text'}(trim($Description, "\n"))
+            );
+            // unset($Block['description']);
+        }
+        if ($this->imageAttributesOnParent) {
+            $Inline = $Block['element']['elements'][0];
+            if ($this->imageAttributesOnParent === true) {
+                $this->imageAttributesOnParent = array_keys($Inline['element']['attributes']);
+            }
+            foreach ((array) $this->imageAttributesOnParent as $Name) {
+                if (isset($Inline['element']['attributes'][$Name])) {
+                    // Merge class names
+                    if (
+                        $Name === 'class' &&
+                        isset($Block['element']['attributes'][$Name]) &&
+                        isset($Inline['element']['attributes'][$Name])
+                    ) {
+                        $Classes = array_merge(
+                            explode(' ', $Block['element']['attributes'][$Name]),
+                            explode(' ', $Inline['element']['attributes'][$Name])
+                        );
+                        sort($Classes);
+                        $Block['element']['attributes']['class'] = implode(' ', array_unique(array_filter($Classes)));
+                        unset($Block['element']['elements'][0]['element']['attributes'][$Name]);
+                        continue;
+                    }
+                    $Block['element']['attributes'][$Name] = $Inline['element']['attributes'][$Name];
+                    unset($Block['element']['elements'][0]['element']['attributes'][$Name]);
+                }
+            }
+        }
+        return $Block;
+    }
+
+    protected function blockImageContinue($Line, array $Block) {
+        if (isset($Block['complete'])) {
+            return;
+        }
+        if (isset($Block['interrupted'])) {
+            $Block['description'] .= "\n";
+            unset($Block['interrupted']);
+        }
+        if ($Line['indent'] === 0) {
+            $Block['complete'] = true;
+            return;
+        }
+        if ($Line['indent'] > 0 && $Line['indent'] < 4) {
+            $Block['description'] .= "\n" . $Line['text'];
+            return $Block;
+        }
+        return;
+    }
+
+    protected function blockQuoteComplete($Block) {
+        $this->doSetAttributes($Block['element'], $this->blockQuoteAttributes);
+        $this->doSetContent($Block['element'], $this->blockQuoteText, false, 'arguments');
+        return $Block;
+    }
+
+    protected function blockSetextHeader($Line, array $Block = null) {
+        if (!$Block = parent::blockSetextHeader($Line, $Block)) {
+            return;
+        }
+        $Level = $Line['text'][0] === '=' ? 1 : 2;
+        $this->doSetAttributes($Block['element'], $this->headerAttributes, array($Level));
+        $this->doSetContent($Block['element'], $this->headerText, false, 'argument', array($Level));
+        return $Block;
+    }
+
+    protected function blockTableContinue($Line, array $Block) {
+        if (!$Block = parent::blockTableContinue($Line, $Block)) {
+            return;
+        }
+        $Aligns = $Block['alignments'];
+        // `` or ``
+        foreach ($Block['element']['elements'] as $Index0 => &$Element0) {
+            // ``
+            foreach ($Element0['elements'] as $Index1 => &$Element1) {
+                // `` or ``
+                foreach ($Element1['elements'] as $Index2 => &$Element2) {
+                    $this->doSetAttributes($Element2, $this->tableColumnAttributes, array($Aligns[$Index2], $Index2, $Index1));
+                }
+            }
+        }
+        return $Block;
+    }
+
+    protected function blockTableComplete($Block) {
+        $this->doSetAttributes($Block['element'], $this->tableAttributes);
+        return $Block;
+    }
+
+    protected function buildFootnoteElement() {
+        $DefinitionData = $this->DefinitionData['Footnote'];
+        if (!$Footnotes = parent::buildFootnoteElement()) {
+            return;
+        }
+        $DefinitionKey = array_keys($DefinitionData);
+        $DefinitionData = array_values($DefinitionData);
+        $this->doSetAttributes($Footnotes, $this->footnoteAttributes);
+        foreach ($Footnotes['elements'][1]['elements'] as $Index0 => &$Element0) {
+            $Name = $DefinitionKey[$Index0];
+            $Count = $DefinitionData[$Index0]['count'];
+            $Args = array(is_numeric($Name) ? (float) $Name : $Name, $Count);
+            $this->doSetAttributes($Element0, $this->footnoteBackReferenceAttributes, $Args);
+            foreach ($Element0['elements'] as $Index1 => &$Element1) {
+                if (!isset($Element1['elements'])) {
+                    continue;
+                }
+                $Count = 0;
+                foreach ($Element1['elements'] as $Index2 => &$Element2) {
+                    if (!isset($Element2['name']) || $Element2['name'] !== 'a') {
+                        continue;
+                    }
+                    $Args[1] = ++$Count;
+                    $this->doSetAttributes($Element2, $this->footnoteBackLinkAttributes, $Args);
+                    $this->doSetContent($Element2, $this->footnoteBackLinkHtml, false, 'rawHtml');
+                }
+            }
+        }
+        return $Footnotes;
+    }
+
+    protected function doGetAttributes($Element) {
+        if (isset($Element['attributes'])) {
+            return (array) $Element['attributes'];
+        }
+        return array();
+    }
+
+    protected function doGetContent($Element) {
+        if (isset($Element['text'])) {
+            return $Element['text'];
+        }
+        if (isset($Element['rawHtml'])) {
+            return $Element['rawHtml'];
+        }
+        if (isset($Element['handler']['argument'])) {
+            return implode("\n", (array) $Element['handler']['argument']);
+        }
+        return null;
+    }
+
+    private function doSetLink($Excerpt, $Function) {
+        if (!$Inline = call_user_func('parent::' . $Function, $Excerpt)) {
+            return;
+        }
+        $this->doSetAttributes($Inline['element'], $this->linkAttributes, array($this->isLocal($Inline['element'], 'href')));
+        $this->doSetData($this->DefinitionData['Reference'], $this->referenceData);
+        return $Inline;
+    }
+
+    protected function doSetAttributes(&$Element, $From, $Args = array()) {
+        $Attributes = $this->doGetAttributes($Element);
+        $Content = $this->doGetContent($Element);
+        if (is_callable($From)) {
+            $Args = array_merge(array($Content, $Attributes, &$Element), $Args);
+            $Element['attributes'] = array_replace($Attributes, (array) call_user_func_array($From, $Args));
+        } else {
+            $Element['attributes'] = array_replace($Attributes, (array) $From);
+        }
+    }
+
+    protected function doSetContent(&$Element, $From, $Esc = false, $Mode = 'text', $Args = array()) {
+        $Attributes = $this->doGetAttributes($Element);
+        $Content = $this->doGetContent($Element);
+        if ($Esc) {
+            $Content = parent::escape($Content, true);
+        }
+        if (is_callable($From)) {
+            $Args = array_merge(array($Content, $Attributes, &$Element), $Args);
+            $Content = call_user_func_array($From, $Args);
+        } else if (!empty($From)) {
+            $Content = sprintf($From, $Content);
+        }
+        if ($Mode === 'arguments') {
+            $Element['handler']['argument'] = explode("\n", $Content);
+        } else if ($Mode === 'argument') {
+            $Element['handler']['argument'] = $Content;
+        } else {
+            $Element[$Mode] = $Content;
+        }
+    }
+
+    protected function doSetData(&$To, $From) {
+        $To = array_replace((array) $To, (array) $From);
+    }
+
+    protected function element(array $Element) {
+        if (!$Any = parent::element($Element)) {
+            return;
+        }
+        if (substr($Any, -3) === ' />') {
+            if (is_callable($this->voidElementSuffix)) {
+                $Attributes = $this->doGetAttributes($Element);
+                $Content = $this->doGetContent($Element);
+                $Suffix = call_user_func_array($this->voidElementSuffix, [$Content, $Attributes, &$Element]);
+            } else {
+                $Suffix = $this->voidElementSuffix;
+            }
+            $Any = substr_replace($Any, $Suffix, -3);
+        }
+        return $Any;
+    }
+
+    protected function inlineCode($Excerpt) {
+        if (!$Inline = parent::inlineCode($Excerpt)) {
+            return;
+        }
+        $this->doSetAttributes($Inline['element'], $this->codeAttributes);
+        $this->doSetContent($Inline['element'], $this->codeHtml, true);
+        $Inline['element']['rawHtml'] = $Inline['element']['text'];
+        $Inline['element']['allowRawHtmlInSafeMode'] = true;
+        unset($Inline['element']['text']);
+        return $Inline;
+    }
+
+    protected function inlineFootnoteMarker($Excerpt) {
+        if (!$Inline = parent::inlineFootnoteMarker($Excerpt)) {
+            return;
+        }
+        $Name = null;
+        if (preg_match('/^\[\^(.+?)\]/', $Excerpt['text'], $matches)) {
+            $Name = $matches[1];
+        }
+        $Args = array(is_numeric($Name) ? (float) $Name : $Name, $this->DefinitionData['Footnote'][$Name]['count']);
+        $this->doSetAttributes($Inline['element'], $this->footnoteReferenceAttributes, $Args);
+        $this->doSetAttributes($Inline['element']['element'], $this->footnoteLinkAttributes, $Args);
+        $this->doSetContent($Inline['element']['element'], $this->footnoteLinkHtml, false, 'text', $Args);
+        $Inline['element']['element']['rawHtml'] = $Inline['element']['element']['text'];
+        $Inline['element']['element']['allowRawHtmlInSafeMode'] = true;
+        unset($Inline['element']['element']['text']);
+        return $Inline;
+    }
+
+    protected function inlineImage($Excerpt) {
+        if (!$Inline = parent::inlineImage($Excerpt)) {
+            return;
+        }
+        $this->doSetAttributes($Inline['element'], $this->imageAttributes, array($this->isLocal($Inline['element'], 'src')));
+        return $Inline;
+    }
+
+    protected function inlineLink($Excerpt) {
+        return $this->doSetLink($Excerpt, __FUNCTION__);
+    }
+
+    protected function inlineText($Text) {
+        $this->doSetData($this->DefinitionData['Abbreviation'], $this->abbreviationData);
+        return parent::inlineText($Text);
+    }
+
+    protected function inlineUrl($Excerpt) {
+        return $this->doSetLink($Excerpt, __FUNCTION__);
+    }
+
+    protected function inlineUrlTag($Excerpt) {
+        return $this->doSetLink($Excerpt, __FUNCTION__);
+    }
+
+    protected function isLocal($Element, $Key) {
+        $Link = isset($Element['attributes'][$Key]) ? (string) $Element['attributes'][$Key] : null;
+        if (
+            // ``
+            $Link === "" ||
+            // ``
+            // ``
+            // ``
+            // ``
+            // ``
+            strpos('./?&#', $Link[0]) !== false && strpos($Link, '//') !== 0 ||
+            // ``
+            strpos($Link, 'data:') === 0 ||
+            // ``
+            strpos($Link, 'javascript:') === 0 ||
+            // ``
+            strpos($Link, 'mailto:') === 0
+        ) {
+            return true;
+        }
+        if (isset($_SERVER['HTTP_HOST'])) {
+            $Host = $_SERVER['HTTP_HOST'];
+        } else if (isset($_SERVER['SERVER_NAME'])) {
+            $Host = $_SERVER['SERVER_NAME'];
+        } else {
+            $Host = "";
+        }
+        // ``
+        if (strpos($Link, '//') === 0 && strpos($Link, '//' . $Host) !== 0) {
+            return false;
+        }
+        if (
+            // ``
+            strpos($Link, 'https://' . $Host) === 0 ||
+            // ``
+            strpos($Link, 'http://' . $Host) === 0
+        ) {
+            return true;
+        }
+        // ``
+        return strpos($Link, '://') === false;
+    }
+
+    protected function parseAttributeData($attributeString) {
+        // Allow compact attributes
+        $attributeString = strtr($attributeString, array(
+            '#' => ' #',
+            '.' => ' .'
+        ));
+        if (strpos($attributeString, '="') !== false || strpos($attributeString, "='") !== false) {
+            $attributeString = preg_replace_callback('#([-\w]+=)(["\'])([^\n]*?)\2#', function($matches) {
+                $value = strtr($matches[3], array(
+                    ' #' => '#',
+                    ' .' => '.',
+                    ' ' => "\x1A"
+                ));
+                return $matches[1] . $matches[2] . $value . $matches[2];
+            }, $attributeString);
+        }
+        $Attributes = array();
+        foreach (explode(' ', $attributeString) as $v) {
+            if (!$v) {
+                continue;
+            }
+            // `{#foo}`
+            if ($v[0] === '#' && isset($v[1])) {
+                $Attributes['id'] = substr($v, 1);
+            // `{.foo}`
+            } else if ($v[0] === '.' && isset($v[1])) {
+                $Attributes['class'][] = substr($v, 1);
+            // ~
+            } else if (strpos($v, '=') !== false) {
+                $vv = explode('=', $v, 2);
+                // `{foo=}`
+                if ($vv[1] === "") {
+                    if ($vv[0] === 'class') {
+                        continue;
+                    }
+                    $Attributes[$vv[0]] = "";
+                // `{foo="bar baz"}`
+                // `{foo='bar baz'}`
+                } else if ($vv[1][0] === '"' && substr($vv[1], -1) === '"' || $vv[1][0] === "'" && substr($vv[1], -1) === "'") {
+                    $values = stripslashes(strtr(substr(substr($vv[1], 1), 0, -1), "\x1A", ' '));
+                    if ($vv[0] === 'class' && isset($Attributes[$vv[0]])) {
+                        $values = explode(' ', $values);
+                        $Attributes[$vv[0]] = array_merge($Attributes[$vv[0]], $values);
+                    } else {
+                        $Attributes[$vv[0]] = $values;
+                    }
+                // `{foo=bar}`
+                } else {
+                    if ($vv[0] === 'class' && isset($Attributes[$vv[0]])) {
+                        $Attributes[$vv[0]] = array_merge($Attributes[$vv[0]], [$vv[1]]);
+                    } else {
+                        $Attributes[$vv[0]] = $vv[1];
+                    }
+                }
+            // `{foo}`
+            } else {
+                if ($v === 'class' && isset($Attributes[$v])) {
+                    continue;
+                }
+                $Attributes[$v] = $v;
+            }
+        }
+        if (isset($Attributes['class'])) {
+            $Attributes['class'] = implode(' ', array_unique((array) $Attributes['class']));
+        }
+        return $Attributes;
+    }
+
+}
diff --git a/module/common/model.php b/module/common/model.php
index 9bda4e3b14..e1141b7368 100644
--- a/module/common/model.php
+++ b/module/common/model.php
@@ -3276,11 +3276,13 @@ EOD;
         if(empty($markdown)) return false;
 
         global $app;
-        $app->loadClass('michelf');
+        $app->loadClass('parsedownextraplugin');
 
-        $Michelf = new michelf;
+        $Parsedown = new parsedownextraplugin;
 
-        return $Michelf->parse($markdown);
+        $Parsedown->voidElementSuffix = '>'; // HTML5
+
+        return $Parsedown->text($markdown);
     }
 }