I recently added VisualEditor to my Wikis. A user reports that when editing and saving a page with a Media link like
[[Media:sample.pdf|download]]
it is transformed to
[[index.php?title=Media:sample.pdf|download]]
which breaks the link. As mentioned in T198511, using Special/Filepath instead is safe.
This happens with MediaWiki 1.39.6 and VisualEditor 0.1.2.