go to your browser a write about:config in the url address in the search bar write : Sync , you will see a feature services.syn.enable make it true

hi, unfortunately this is currently a known issue in firefox 50 when you have set the browser to run in permanent private browsing mode ("never remember history" in the options > privacy panel). firefox developers are working to get this fixed in upcoming versions again...

Settings for privacy, browsing history and do-not-track

Thanks for the replies. However:-

sudanisayfree, I cannot find that setting

philipp, seriously? How pathetic is that? How long is it going to take to fix it?

On another note, now that I have changed my settings to "Remember History" and have successfully logged in, can someone please tell me why it is now NOT syncing??