Starting a few minutes ago, questions tagged "etymology" are highlighted in blue when I visit german.sx.
Yes, I did find the question "Why do some questions in question lists have a yellow background?", but I haven't favourited the "etymology" tag, and I haven't asked or answered any questions with that tag. Is this a bug?
EDIT: The hightlighting just disappeared all by itself. Nevertheless, I won't delete the question yet in case the phenomenon returns.