Firefox Community Forum

Subject: Firefox Sync appears to have erased all bookmarks after setting up a new Windows installation

Hello Mozilla Support,

I believe I have encountered a Firefox Sync issue that resulted in the loss of my entire bookmarks collection.

Here is exactly what happened:

I have been using Firefox Sync for several years without any issues. This was not my first Windows reinstallation. I have restored Firefox through Sync multiple times before. Firefox Sync had always synchronized bookmarks, passwords, history, extensions and open tabs correctly across my Windows PC and Android phone. I had approximately 350 bookmarks, organized into folders. Timeline Yesterday I performed a clean installation of Windows 11. I installed Firefox 152.0.5 (64-bit). I signed into my existing Firefox Account. I did not immediately enable Sync, so nothing was synchronized at that point. Today I enabled Sync and waited for the synchronization to complete. Passwords synchronized successfully. Browsing history synchronized successfully (it took a little longer). Extensions were restored successfully. Bookmarks never appeared.

Immediately after noticing this, I checked Firefox on my Android phone.

At first, one of the bookmark folders still showed that it contained more than 300 items (I saw the item count), but when I opened the folder it was completely empty. After synchronization finished, all bookmarks disappeared from both devices.

Additional information Browsing history is still present. Saved passwords are still present. Extensions are still present. Open tabs synchronization continues to work. Bookmark synchronization is enabled. I am signed into the correct Firefox Account. The second local Firefox profile is empty. The automatic bookmark backup now contains only the current state (7 items), indicating that the original backup has already been overwritten. The current profile contains both places.sqlite and places.sqlite-wal. The only Sync error log is related to a temporary DNS lookup failure (NS_ERROR_UNKNOWN_HOST) and contains no bookmark synchronization errors.

Because history, passwords and extensions synchronized correctly, this does not appear to be an account or authentication problem.

What concerns me most is that I briefly saw the bookmark folder still reporting over 300 items on Android before it became empty. This makes me suspect that something went wrong during bookmark synchronization rather than the bookmarks simply never existing on the server.

Could you please advise:

Is there any server-side recovery or investigation that can be performed for Firefox Sync bookmark data? Are there any diagnostic logs that I can provide? Is this a known issue with Firefox Sync after connecting a newly installed device?

I would greatly appreciate any assistance, as this bookmark collection had been accumulated over many years.

I have a Sync error log available: error-sync-1783454370913.txt

It only contains a DNS error related to tabs synchronization: NS_ERROR_UNKNOWN_HOST

There are no bookmark-related errors in the log.

Thank you.

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Moderator note: "Edited for language"

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