Bloody hell. I waited a few weeks to upgrade to Firefox 1.5 (MacOSX), because I know from bitter experience that every single time the bloody thing is upgraded, something breaks. I figure the early adopters run interference for me. Well, it appears I have to wait even longer -- it took about five minutes after upgrading for me to run in to Bug 298502, which is where you get the Beachball of Death and have to force-quit the second (but not the first) time you try to use a drop-down from the bookmarks toolbar. It seems to have been around since June, so that must have been on 1.0.x builds, but I'm back on 1.0.7 now and it's not happening. Gaaaah.