Someone who unfriended me on Facebook a while back just tried to tag someone I don't know in a photo I took at a mutual friend's birthday party a few years ago. If he were in the photo, that would be fine, but he's not. The photo is of the person who unfriended me, and her then-boyfriend.
I'm not sure I feel much need to interact at all with someone who unfriended me (it was a shame, but not traumatic, since we were only casual friends), but this seems especially weird behavior. Blocking her would probably be an overreaction, but I feel a little odd approving the tag, of someone I don't know, in a photo he's not in.