modules/main/templates/_textarea.inc.php has two links pointing to URLs under issues.thebuggenie.com without preceding http:// protocol, resulting in non-working links.

$ grep 'href="issues' core/modules/main/templates/_textarea.inc.php 
                 'MarkdownFormatting')); ?>
                 'MarkdownFormatting')); ?>

1. Open a text area, for example to report a new issue
2. Have Markdown as Selected syntax
3. Have the ”See more formatting tips in MarkdownFormatting” tip appear (I don’t know the exact steps to trigger this)
   4. Try to open the MarkdownFormatting link