I can't see the SYNC option in Settings so I... Use about:config to change identity.fxaccounts.enabled = true I can now see 'Sync' in Settings When I go to "Sign into Sync", after I enter my password, it hangs for 10 seconds, then says Working, then always just hangs there forever. If I login to Mozilla using a different tab, it signs in ok. I have tried this after successfully changing the password, and after restarting firefox. I am using the latest Firefox version. Any suggestions gratefully accepted.