A few days ago links in messages stopped working in Outlook (Microsoft 365) on my Windows 10 Pro 64-bit PC. Good ol' Microsoft support reset Firefox on the PC and I lost all bookmarks, history and personalized settings. Tried to copy data from Old Firefox Data file into profile on reset Firefox. Didn't work. Uninstalled and reinstalled Firefox and tried to copy data from old profile to new profile. Nada. Only option now is to try to sync Firefox on my Mac to new install on PC. I'll still lose some bookmarks and history but it will be better than what I have now. I have a Firefox account on both devices but when I log in to Firefox on the Mac I cannot find anything pertaining to sync. Problem one: how do I navigate to sync in Firefox for Mac. Problem two: when I bought the Mac 6 years ago I tried to sync Firefox on my PC to the new Mac. For some reason Firefox synced the empty new profile on the Mac to the old PC. I lost all bookmarks and history accumulated on the old PC! I do not want to go through that again. I have never found anything on Mozilla that clearly explains how to control which way the sync works. Must be certain that I'm copying all the bookmarks, history, tabs etc, from the old device to the new on and not vice versa.