Title says it all. When editing a post you get the modal. If you click on "more" and get to the actual edit page, the style chooser button and the language chooser button are gone on default style. I recognized the same with UIX, but there the language chooser remains and only the style chooser...
What does this add-on do?
This add-on provides additional options to manage the Language Chooser through the Admin Control Panel:
Move the Language Chooser to extra locations
Allow Language Chooser on pages where it is not visible, including during account registration