Error
Request ID: W@JHKwpAMEQAACQYxLgAAABL
MediaWiki\Revision\RevisionAccessException: Could not determine title for page ID # and revision ID # from line 391 of /srv/mediawiki/php-1.32.0-wmf.26/includes/Revision/RevisionStore.php
#0 /srv/mediawiki/php-1.33.0-wmf.1/includes/Revision/RevisionStore.php(379): MediaWiki\Revision\RevisionStore->getTitle(integer, integer, integer) #1 /srv/mediawiki/php-1.33.0-wmf.1/includes/Revision/RevisionStore.php(2531): MediaWiki\Revision\RevisionStore->getTitle(integer, integer) #2 /srv/mediawiki/php-1.33.0-wmf.1/includes/api/ApiComparePages.php(68): MediaWiki\Revision\RevisionStore->getPreviousRevision(MediaWiki\Revision\RevisionArchiveRecord) #3 /srv/mediawiki/php-1.33.0-wmf.1/includes/api/ApiMain.php(1570): ApiComparePages->execute() #4 /srv/mediawiki/php-1.33.0-wmf.1/includes/api/ApiMain.php(531): ApiMain->executeAction() #5 /srv/mediawiki/php-1.33.0-wmf.1/includes/api/ApiMain.php(502): ApiMain->executeActionWithErrorHandling() #6 /srv/mediawiki/php-1.33.0-wmf.1/api.php(87): ApiMain->execute() #7 /srv/mediawiki/w/api.php(3): include(string)
Impact
It seems that for certain revisions, users are unable to obtain comparison information from the API. Specifically, archived revisions (possibly limited to those that are oversighted).
Notes
Reported in WMF Logstash 204 times in recent weeks (since 1.32.wmf-24, possibly earlier).
It is seen from multiple different wikis for a wide range of different page IDs and revisions. The referer for many of them are like https://en.wikipedia.org/wiki/Special:Log/suppress which suggests it might be triggered by a gadget attempting to provide information from the API about revisions in the log.
I don't know if comparing oversighted/archived revisions is currently supported in the API, but at least it shouldn't fatal.