Every time I start Firefox, Sync has logged me out and I have to re-setup Sync for it to begin syncing my data. When I forget to do this, I get to my other machine only to realize my bookmarks aren't synced. My settings dictate that almost everything is cleared (History, Passwords, etc) each time I close the browser, but I didn't think my Sync login would be part of that (and maybe the problem has nothing to do with that). This is happening on multiple desktops, both Macs and PCs, all of which share similarly strict "clear from memory" settings each time FF is closed.