Nov 27 2016
Oct 21 2015
@matmarex, I don't have Opera12. Can you test the articles on hewiki and enwiki (those that seem to have the problem and those that seem to not have the problem) and see if they manifest they have a redirect loop with Opera12?
Oct 20 2015
Thanks. The cut-off here seems to be at around Jul-10 or slightly later. I'm not completely sure.
On which other wikis do we have this problem? We seem to have it on enwiki as well. From which time, exactly? Is it the same time as hewiki? How can I find out? @IKhitron, can you provide a similar query for enwiki?
It seems that the issue started (at least in hewiki) on Jul 22, perhaps around noon (local time):