Should we strip user:me and show those results after (an edited version of) this message? You'd still get something, and maybe that was enough or maybe you need to log in now and try again.

For me personally, I'd rather be shown no results and an explanation of why, than some results that I might go straight into looking through without noticing the message that warns me about them being different from expected. I'd like to avoid that potential for wasting the user's time.

Perhaps we could include a clearly labelled link to those non-user-specific results below the initial message, so the potentially misleading results are only seen if the user explicitly chooses them. We should probably omit this option if user:me was the only search term (otherwise the link would be to a search with an empty search term, showing all posts in the results).