In T253125 we realized that prefetching wasn't working correctly.
We were planing on the terms related prefetching always resulting in correctly prefetched entities, however, that prefetching did not happen in time for some needed data, thus when we switched to requiring prefetching, we got exceptions as things were not prefetched in time. (see the ticket filed).
In T253125#6162897 we performed a task breakdown where we were thinking about using EntityInfo for prefetching, however, shortly after the breakdown we realized that EntityInfo is not really used any more and already should have been removed (see a big comment at T253125#6163636 and also T254283: Remove legacy EntityInfo based prefetching that has now been created).
Prefetching of properties should happen when:
- Entity pages are rendered
- Pages with edit summaries that we format are rendered
Other links and reading
- Breakdown from the previous hike when EntityInfo was still a thing T253125#6162897
- Previous EntityInfo based prefetching collected referenced entities for prefetching in parser output generator https://gerrit.wikimedia.org/r/c/mediawiki/extensions/Wikibase/+/604121/8/repo/includes/ParserOutput/FullEntityParserOutputGenerator.php#b197