minor #3566 Update markdown-to-html converter missing message (tobias-93)
minor #3566 Update markdown-to-html converter missing message (tobias-93)

This PR was submitted for the 3.x branch but it was merged into the 2.x branch instead.

Discussion
----------

Update markdown-to-html converter missing message

The `league/html-to-markdown` library does not support Markdown to HTML conversion (anymore?). The `league/commonmark` library is suitable for that.

Commits
-------

46d21545 Update markdown-to-html converter missing message

twigphp/Twig,twigphp/Twig,twigphp/Twig