I initially posted this question (on a meta site where I was and still am a moderator) with the
featured tag. The tag since then expired, and just now I tried adding it back. I used the “secret
edit tags button”, which may or may not matter. Now the question is in a strange state: it doesn't have the
but the tag is there in the question editor!
(I've refrained from further editing the question, in case investigation is needed.)