The language selector now surfaces languages you may want to translate (T290972). A message ( "Missing in X, Y and more") invites users to translate into the language they frequently use in which the article is not available yet.
The initial implementation provide the key functionality, but there are some details to polish. In particular, the current implementation keeps the invite visible when searching while it was only intended to be visible with the non-filtered list.
The message is not sticky or floating (it just scrolls up with the language list) and it is not shown in the results while searching. In this way users can focus on language selection if they are not interested in the action.
Currently the message remains visible when the user searches for a language (on both cases when there is a result and when there is not). This is not ideal since the user searching to find another language indicates their interest on the languages they search for. So at that point the invite is just getting in the way.
This ticket proposes for the invite to be hidden when the user searches.