XZise added a comment.
Okay as far as I can see, it is querying the server and gets bytes back but then it tries to apply a regex and to do that it apparently needs to decode the bytes and it's using the ASCII codec for that. I'm not 100 % sure why it tries to decode it here and why it had worked before (I guess T89589: Usage of unicode_literals from __future__ package https://phabricator.wikimedia.org/T89589 plays a role). I need to take a closer look on how to fix that properly.
TASK DETAIL https://phabricator.wikimedia.org/T94688
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To: XZise Cc: Ricordisamoa, jayvdb, XZise, Aklapper, Rubin16, pywikipedia-bugs