In the wikibase release pipeline we've added [[ https://github.com/wmde/wikibase-release-prototype/pull/38/files#diff-312a30198e1d9164989f542dc57aec3d9b8b574420d2ee8847fd1780bf27667c | some tests ]] that check that the client repo setup works correctly (referencing items, dispatching changes etc)
These tests started failing once https://phabricator.wikimedia.org/T272485 was merged into master.
Interestingly the tests didn't fail in any catastrophic way but any requests that was made from selenium were just left hanging without any response. I tried using the UI(wdio) & the API (wdio-mediawiki) in the tests but with the same result.
A part from the tests failing a new deprecation warning also started showing under certain circumstances like the one showed below.
I was able to make the tests pass locally by applying a patch like [[ https://gerrit.wikimedia.org/r/c/mediawiki/extensions/Wikibase/+/661114 | this ]] but I suspect there may be many more cases where this could occur as RevisionRecord::getId is called all over the place.