I think this may be the same issue with not translated strings, this time in Polish version. See the picture.

notTranslated-preview inactive survey.jpg (66,969 bytes)   

notTranslated-preview inactive survey.jpg (66,969 bytes)   

@LouisGac : there are no string for gT function inside twig file.
https://translate.limesurvey.org/projects/limesurvey-3/fr/default/?filters%5Bterm%5D=This+survey+is+currently+not+active&filters%5Buser_login%5D=&filters%5Bstatus%5D=current_or_waiting_or_fuzzy_or_untranslated&filter=Filter&sort%5Bby%5D=priority&sort%5Bhow%5D=desc

This is surely the limesurvey-translations script : search only applications directory maybe. This is really a major issue , can you have a look at the script ?
https://github.com/LimeSurvey/LimeSurvey/commits?author=limesurvey-translations

See https://github.com/LimeSurvey/LimeSurvey/blob/master/locale/_template/limesurvey.pot

I find more untranslated strings. Should I report them here or in a new issue? Here is an example from the theme settings screen.

translationlack1.jpg (90,194 bytes)   

translationlack1.jpg (90,194 bytes)   

Unsure about theme setting : i think theme need a dedicated po file too :)

Hello,
there is still an untraslated string in LS 3.22.25,
It's the "Inherit everything" Label in Survey option page.
I see in the demo site version (4.2.1) it's ok but I cannot tell if this is fixed for latest 3.X LTS.

immagine.png (32,950 bytes)   

immagine.png (32,950 bytes)   

Yes, it's still untraslated I am afraid.
There is no "Inherit everything" string to translate in the translation site.