How to stop Sync tab? When open firefox it also opens tab asking to sign up to Sync.
When click on Firefoxon browser to open it now automatically check add on compatability everytime ,never used to do this. Only started doing this since on Firefox start up it opens one tab for designated homepage and another for Firefox sync join up page. How do I stop It opening SYNC sign up page. All I want is for homepage to show. Cheers if you can help
الحل المُختار
hello, this might happen when firefox is not able to properly save preferences in its profile folder. please try this: Click the menu button 
and then click help 
> troubleshooting information > profile folder - "show folder". then a new window will open up. in this window look out for a file named user.js (it might be used to overwrite your custom settings). in case it is present , delete or rename this file and restart firefox afterwards.
for more information and other steps please also see: How to fix preferences that won't save
Read this answer in context 👍 0All Replies (8)
Hey Shaunnie,
If you take a look at the screenshot I've included in my reply, could you check your settings are set to the same?
When Firefox starts -> Show my home page
Home page -> Whichever site you wish to be default (or, click Restore to Default, to use the Firefox start page)
Let us know how you get on!
Modified by Seblirium
Hi Yes have set homepage to google. It does go there but another tab opens aswell with the sync join page. I have no wish to join firefox sync. It also causes firefox to check addons everytime it starts which it didn`t before Frustrating. But thankyou for reply
الحل المُختار
hello, this might happen when firefox is not able to properly save preferences in its profile folder. please try this: Click the menu button and then click help > troubleshooting information > profile folder - "show folder". then a new window will open up. in this window look out for a file named user.js (it might be used to overwrite your custom settings). in case it is present , delete or rename this file and restart firefox afterwards.
for more information and other steps please also see: How to fix preferences that won't save
Hi Had a look and no file of that name user.js present. Will try the Hiow to fix preferences that won`t save . Section next Thanks for your help
Delete a possible user.js file and numbered prefs-##.js files and rename (or delete) the prefs.js file to reset all prefs to the default value including prefs set via user.js and prefs that are no longer supported in the current Firefox release.
Thanks for all your help on the forum. searched for all prefs files and deleted them and seems to have worked. so a big thankyou for all your advice
Deleting prefs.js (or more precisely renaming it) stopped the bad behavior, but at the cost of having to reset massive amounts of stuff - my appearance, extensions, etc all appear to be there, but aren't in effect.
Way to big a hammer - you need a much better solution to the problem of how to get rid of a sync account when you no longer need it.
It shouldn't be necessary to delete the prefs.js file.
Did you check the setting to make sure that you aren't opening those pages?
This issue can also be caused by a problem with the compatibility.ini file.
There is software like Advanced SystemCare with its Surfing Protection feature that can protect files in the Firefox profile folder against changes. If you have such software then check the settings or uninstall this software.