I have 3 PCs on my home network (two Windows 8.1 and one old Windows XP (SP3) ) all running Firefox 35.0.1, all connected to the internet. I created a sync account and activated Sync (I assume the new one, since I never used it before). I think it's working, but today I created a bookmark folder and added a bookmark to it on the Windows XP PC. So far that folder and bookmark have not shown up anywhere else. So questions: 1) Does Firefox have to remain open on all PCs for sync to work? 2) How often does Sync sync? 3) If i click Sync now on the PCs (the one with the new data first) should they sync immediately? PS: I'm asking this question from one of the Windows 8.1 PCs so the shared data is from that PC.