Where is the discussion and review of ContentHandler?
ContentHandler is something I'd really like to see make it into core. It's useful for far more than just Wikidata. I'd like to comment and review some part of the code. Like method naming patterns that don't match the patterns we use elsewhere in core. And coding patterns/assumptions that don't seem to leave room for some of the rationales ContentHandler was created for. But the ContentHandler code is spread out over many pre-accepted commits, and that that it's not even part of a dedicated branch so it's hard to find the relevant commits amongst the pile of Wikidata commits.
https://www.mediawiki.org/wiki/ContentHandler https://gerrit.wikimedia.org/r/gitweb?p=mediawiki/core.git;a=blob;f=includes... https://gerrit.wikimedia.org/r/gitweb?p=mediawiki/core.git;a=blob;f=includes...