When searching through favorites, if you have a favorited post that was deleted, you have to put status:deleted into the query to be able to see it. Enabling "show deleted posts" in account settings would solve this, but comes with the side effect of pulling up low-quality whatever when searching outside of favorites, which kind of defeats the point.
Proposal: "ordfav" and "fav" search queries should also automatically pull up deleted posts. If it's in your favorites then you probably wanted to see it anyways.