I am experiencing some strange behaviour with Firefox's automatic completion feature. It only seems to happen with the hours. For example, I will get two instances of "2 AM" along with a "2 PM". If I delete the second 2 AM they both disappear, leaving only the 2 PM. So I infer from this that it is a display problem rather than a duplication in the list Firefox maintains for each cell. I rebooted and it seemed to fix the problem at first, but it didn't. It's strange that this has just begun to happen. I do remember a few days ago Firefox flashed a message telling me it was checking my add-ons. Perhaps it changed something then. Has anyone else experienced this?