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Firefox not syncing new PC with OLD PC open tabs

  • 2 replies
  • 1 has this problem
  • 24 views
  • Last reply by cor-el

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I have built a new PC. Both PC's are logged into the same Firefox Account.

The old PC has over 100 tabs open I need to have open on the new PC.

When I sync, it does not open the old PC tabs on the new PC.

I will need to use the old PC C drive eventually as the new PC D drive, but obviously cannot do so until the New PC has all the tabs open from the Old PC.

I cleared the browser console before attempting a sync - there are no error messages generated in the browser console after I tried to sync.

Please advise

I have built a new PC. Both PC's are logged into the same Firefox Account. The old PC has over 100 tabs open I need to have open on the new PC. When I sync, it does not open the old PC tabs on the new PC. I will need to use the old PC C drive eventually as the new PC D drive, but obviously cannot do so until the New PC has all the tabs open from the Old PC. I cleared the browser console before attempting a sync - there are no error messages generated in the browser console after I tried to sync. Please advise

All Replies (2)

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The following is based on Sync'ing Firefox on Android with Firefox on Windows.

On Windows, I have a new sidebar called Synced Tabs which lists all the tabs from Firefox on Android. I can open them individually or, if I'm incredibly patient, I can open them all at once by right-clicking the device name and using Open All in Tabs. Do you have that? Here's the article on sidebars for reference:

Use the Firefox Sidebar to access bookmarks, history and synced tabs

I do think you need to either open them or bookmark them before you disconnect your old Firefox, that this list is updated in real-time and isn't stored on your new Firefox.

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Note that you can also backup sessionstore.jsonlz4 in the Firefox profile folder to habe a copy of your currently open tabs.

You can copy/backup certain files with Firefox closed to the current profile folder to transfer or recover personal data. Note that best is to avoid copying a full profile folder.

You can use the button on the "Help -> More Troubleshooting Information" (about:support) page to go to the current Firefox profile folder or use the about:profiles page.


  • bookmarks and history: places.sqlite
  • favicons: favicons.sqlite
  • bookmark backups: compressed .jsonlz4 JSON backups in the bookmarkbackups folder
  • cookies.sqlite for the Cookies
  • formhistory.sqlite for saved autocomplete Form Data
  • logins.json (encrypted logins;32+) and key4.db (decryption key;58+) for Passwords saved in the Password Manager
    key3.db support ended in 73+; to use key3.db in 58-72, make sure to remove key4.db
  • cert9.db (58+) for (intermediate) certificates stored in the Certificate Manager
  • persdict.dat for words added to the spell checker dictionary
  • permissions.sqlite for Permissions and possibly content-prefs.sqlite for other website specific data (Site Preferences)
  • sessionstore.jsonlz4 for open tabs and pinned tabs (see also the sessionstore-backups folder)