I saw my own question in the recently active question lists as this:
And I wonder what caused this specific user to show up as having modified it. I know that edits, and (deleted) answers cause a question to be modified, but I, as OP, got no notification of either.
So using the new nifty timeline button, I went to investigate.
Which lead me to this:
Where the question was reopened, and the decisive fifth vote was cast using the mighty dupe hammer.
I can't recall another question that was recently active by re-opening, so is this and edge case cause by wielding the un-dupe hammer?