Can't undo changes using reject changes button in form with button to approve pending changes. Normally, it should bring to page with summary what will be undone and prompt for edit summary. Instead, it shows error message review_reject_nulledits. Edits are not blank. Only applicable when there is only one pending edit; otherwise the edit summary used is broken but the revert is still possible
It affects all wikis with pending changes with form to flag revision or undo using button "reject".
Tracked the cause, patch coming momentarily:
Only affects pages where there is one edit being reverted, but still, pretty much breaks the functionality; also, edit summary is broken when reverting multiple
Change 585618 had a related patch set uploaded (by DannyS712; owner: DannyS712):
[mediawiki/extensions/FlaggedRevs@master] Fix logic for determining if pending edits were null
Possible cause: T246284 rEFLR46291eda776f722ffe61b2a0904e11ea6cd5f014
https://gerrit.wikimedia.org/r/#/c/mediawiki/extensions/FlaggedRevs/+/584639/
Tagging team and reviewer of that change.
@DannyS712 Have you confirmed the problem on your local mediawiki install?
I don't have flagged revs locally installed, unfortunately, but I walked through line by line tracking what the variables should be by hand and comparing the state before and after my code above, and this was the issue
Change 585618 merged by jenkins-bot:
[mediawiki/extensions/FlaggedRevs@master] Fix logic for determining if pending edits were null
Change 585621 had a related patch set uploaded (by DannyS712; owner: DannyS712):
[mediawiki/extensions/FlaggedRevs@wmf/1.35.0-wmf.26] Fix logic for determining if pending edits were null
Change 585621 merged by jenkins-bot:
[mediawiki/extensions/FlaggedRevs@wmf/1.35.0-wmf.26] Fix logic for determining if pending edits were null
Mentioned in SAL (#wikimedia-operations) [2020-04-03T00:42:44Z] <catrope@deploy1001> Synchronized php-1.35.0-wmf.26/extensions/FlaggedRevs/: Fix logic for determining if pending edits were null (T249277) (duration: 01m 00s)