Today Nikerabbit discovered https://bugzilla.wikimedia.org/52702 has been fixed recently, IMHO great news. So, a reminder of what you can do when you see a broken/improvable MediaWiki translation (especially for the oldtimers used to old workflows).
1) Copy the message text you want to improve or memorise some words of it (not more than this, please!) 2) Search (1) with the search box at a) https://translatewiki.net/wiki/Special:SearchTranslations or b) https://translatewiki.net/wiki/Special:MainPage (it's the same) 3) Refine from there and left-click edit to correct the message in the same page 4) (Optionally) Continue with more messages
Nemo