I noticed an old question of mine had recent activity. It showed up near the top of the list of questions (when I was viewing while logged out). But when I looked at the question, I couldn't figure out what the activity was. All the answers, comments, and "edited by"'s seem old, but something was done "10 hours ago" (see screen shots below).
I welcome editing, just curious sometimes what it is!
For reference, right now the time is:
UPDATE: aha! now I see - Community is a bot(!)(?)