Hello Jakub and Daniel. A problem very similar to the one reported here is happening right now in buster (which I am still tracking for QA purposes). I've put a bunch of build failures here from my own autobuilders:
https://people.debian.org/~sanvila/build-logs/didjvu/ The problem seems timezone-related and it's happening at least since 2019-10-09. I believe that the recent switch from summer time to winter time (which happened today in Europe) may have something to do. Please advise if it's ok to repoen this bug or a new one should be filed instead. Thanks.