Deployed uses outside of core:
[] Wikibase `RepoHooks::onPageHistoryLineEnding`
[] Thanks `ThanksHooks::insertThankLink` - handler for two hooks that will need to be replaced
In core:
[] HistoryPager - https://gerrit.wikimedia.org/r/#/c/mediawiki/core/+/593620/
[] DifferenceEngine - https://gerrit.wikimedia.org/r/#/c/mediawiki/core/+/593272/
[] `Article::showDeletedRevisionHeader`
[] RevDelRevisionItem - https://gerrit.wikimedia.org/r/#/c/mediawiki/core/+/593620/
[] `RevisionItem::isDeleted` - https://gerrit.wikimedia.org/r/#/c/mediawiki/core/+/593620/
[] `SpecialMergeHistory::formatRevisionRow` - https://gerrit.wikimedia.org/r/#/c/mediawiki/core/+/593620/
[] SpecialUndelete - https://gerrit.wikimedia.org/r/#/c/mediawiki/core/+/593620/
[] `DeletedContribsPager::formatRevisionRow` - https://gerrit.wikimedia.org/r/#/c/mediawiki/core/+/593620/
In core tests: RevisionDbTest, RevisionTest