https://test2.wikipedia.org/wiki/Special:AboutTopic/Q140 redirects to https://test2.wikipedia.org/wiki/San_Francisco which is a non-existing (but deleted) page.
It is important to know the page was deleted, so not sure it should just show the placeholder. But could be a link to the placeholder here.
2 options we need to discuss:
I am in favor of the latter.
What happens if the subject is notable enough for Wikidata but isn't for Wikipedia? Newbies would feel encouraged to create the page via the placeholder, over and over again.
Good point, Riccordisamo! We can just not show the create article button if the article has been deleted before? That sounds like a sensible thing to do anyway.