This is the exception message that was happening:
Original exception: exception 'MWException' with message 'Detected bug in an extension! Hook MarkdownExtension::onBeforePageDisplay failed to return a value; should return true to continue hook processing or false to abort.' in /srv/http/mediawiki/includes/Hooks.php:284
This is the exception message that was happening: Original exception: exception 'MWException' with message 'Detected bug in an extension! Hook MarkdownExtension::onBeforePageDisplay failed to return a value; should return true to continue hook processing or false to abort.' in /srv/http/mediawiki/includes/Hooks.php:284
This fixes #3.