diff --git a/app/rendering.php b/app/rendering.php
index 4da9798..5b27ebe 100644
--- a/app/rendering.php
+++ b/app/rendering.php
@@ -14,10 +14,7 @@ function renderContentFile(string $filePath): string {
             if (!class_exists('Parsedown')) {
                 require_once __DIR__ . '/vendor/Parsedown.php';
             }
-            if (!class_exists('ParsedownExtra')) {
-                require_once __DIR__ . '/vendor/ParsedownExtra.php';
-            }
-            $html = '<article>' . (new ParsedownExtra())->text(file_get_contents($filePath)) . '</article>';
+            $html = '<article>' . (new Parsedown())->text(file_get_contents($filePath)) . '</article>';
             setCachedMarkdown($filePath, $html);
             echo $html;
         }
diff --git a/app/vendor/ParsedownExtra.php b/app/vendor/ParsedownExtra.php
deleted file mode 100644
index d192e2b..0000000
--- a/app/vendor/ParsedownExtra.php
+++ /dev/null
@@ -1,686 +0,0 @@
-<?php
-
-#
-#
-# Parsedown Extra
-# https://github.com/erusev/parsedown-extra
-#
-# (c) Emanuil Rusev
-# http://erusev.com
-#
-# For the full license information, view the LICENSE file that was distributed
-# with this source code.
-#
-#
-
-class ParsedownExtra extends Parsedown
-{
-    # ~
-
-    const version = '0.8.0';
-
-    # ~
-
-    function __construct()
-    {
-        if (version_compare(parent::version, '1.7.1') < 0)
-        {
-            throw new Exception('ParsedownExtra requires a later version of Parsedown');
-        }
-
-        $this->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+<dl>\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:$definitionId",
-                        'rev' => 'footnote',
-                        'class' => 'footnote-backref',
-                    ),
-                    'rawHtml' => '&#8617;',
-                    'allowRawHtmlInSafeMode' => true,
-                    'autobreak' => false,
-                );
-            }
-
-            unset($backLinkElements[0]);
-
-            $n = count($textElements) -1;
-
-            if ($textElements[$n]['name'] === 'p')
-            {
-                $backLinkElements = array_merge(
-                    array(
-                        array(
-                            'rawHtml' => '&#160;',
-                            '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]+[ ]*)';
-}
\ No newline at end of file