The VisualEditor welcome screen pops up on Wikibase entity undo pages, where there is no VisualEditor. This is potentially confusing for users, and also recently lead to some failing browser tests for extensions that integrate both with Wikibase and VisualEditor (see T201901).
Screenshot taken on wikidata.org:
FWIW this also happens when manually appending action=edit to any entity page, although that is less problematic.