Diễn đàn hỗ trợ Firefox

Не працює розширення Firefox multi account containers, firefox не бачить моїх налаштованих проксі, контейнери відкриваються не під тими проксі які налаштовані в них

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.

I utilize a website called Twinspires for wagering on horses. It has a video popup (no sidebar tabs) that one can engage to watch the race outside of the Firefox browser. I quite like this feature. That said, I keep quite sidebar tabs saved as I use that feature to pin and then revisit websites that I want to spend more time on. Problem: If the browser closes on its own or other issue, it doesn't close the video popup. So when I restart the browser it "thinks" that video popup, with no saved sidebar tabs, was the last browser open so I lose all my saved sidebar tabs. If everything Firefox would close when the browser does, one could restore all tabs under history like one would normally do. Is there a setting so everything Firefox that is open closes when the browser does? Thank you.

plz guys help me my eyes hurt so bad because of this

every time i open firefox for pc, a white flash appears very quickly

i tried every thing ai told me to, but still

i cant even record it it doesnt appear in video

I lost all bookmarks on or about June 29, 2026 after doing a Firefox update that asked me to create a profile when I'd never had one before. I have not been able to recover them.

I download my share of media using BitTorrent with Pirate Bay. Just lately, every time I attempt to download something I get redirected to a page, https://ultimatesurferprotector.com/lp5.php, that tries to sell me a VPN and I can find no way to stop this or contact them. I am happy with the VPN I have and have no interest in purchasing another. Does anyone know how I can prevent this from happening? Thank you.

MikeQ [email removed from moderator]

Not limited to youtube

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What did I do wrong? how to correct, so that I stop receiving the error message?

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