In the language overlay the links generated are desktop links instead of .m. ones. ~~~And it won't automatically jump to mobile site either.~~~
In the mediaviewer overlay a similar problem:
Visit https://en.m.wikipedia.org/wiki/Book#/media/File%3ABook_Collage.png and click on the "Details" button. You'll be taken to https://commons.wikimedia.org/wiki/File:Book_Collage.png#mw-jump-to-license.
Expected: You should be taken to https://commons.m.wikimedia.org/wiki/File:Book_Collage.png#mw-jump-to-license