T283170 (via T279796) was caused by Wikibase passing Titles into PageProps::getProperties() that don’t represent existing pages (such as special pages). We should probably filter those out in PagePropsEntityIdLookup::getEntityIds(), at least as long as that method is declared to accept a Title. (Eventually we should probably move the EntityIdLookup interface away from the Title class as well.)
This was caused by the message on the italian wikiversity recent changes speciale page being overwritten with something that included Wikibase-Lua.
- PagePropsEntityIdLookup::getEntityIds() (link) should be able to handle Non-PageIdentity titles, like Special Pages, without causing a fatal error.
- i.e. the query should not run for title that do not have page props, like Special Pages