Firefox Community Forum

COPIED FIREFOX BOOKMARKS FROM MY HP COMPUTER TO MY DELL LAPTOP BY COPING THE HTML FILE OF BOOKMARKS TO MY DELL LAPTOP DESKTOP SCREEN AND IMPORTED THEM FROM THE DELL LAPTOP DESKTOP AS ADVISED. STILL DID NOT GET ANYTHING COPIED TO THE NEW FIREFOX INSTALLATION EVEN THOUGH IT STATED IT HAD COPIED 827 BOOKMARKS. NOTICED THAT THE FIREFOX SOFTWARE INSTALLED ON MY HP COMPUTER STATED THAT IT WAS WINDOWS 10 INSTALLATION. ORIGINALLY THE HP WAS WINDOWS 10 BUT UPGRADED IT WITH FREE MICROSOFT WINDOWS 11 BUT DID NOT UNINSTALL FIREFOX FROM IT AND REINSTALL FIREFOX AFTER THAT. THEREFORE THE FIREFOX BOOKMARKS ARE FOR A WINDOWS 10 INSTALL ON THE HP COMPUTER AND TECHNICALLY NOT A WINDOWS 11 EVEN THOUGH THE WINDOWS OS HAD BEEN UPGRADED TO WINDOWS 11. SO, I GUESS TO PERFORM THE ACTION I STATED ABOVE TO UNINSTALL FIREFOX ON THE HP COMPUTER AND REINSTALL IT ON THE HP COMPUTER IT IN ORDER TO GET IT TO WINDOWS 11 FOR BOOKMARKS? HOPEFULLY I WON'T LOSE THOSE FIREFOX BOOKMARKS?

latest update "erased" my bookmarks. Ive followed all instructions, no backup file shows when doing Restore directions. Supposed to automatically save last 15 updates but no bookmarks? Where else may it be saved to try manual restore or am I going to have to reenter all I had.

I made 2 copies of the Firefox backup folder on a Win 10 computer and haven't been able to restore either to a Win11 computer. The error message is "This file isn’t working. Try picking a different file." The Win 10 computer had a later version of Firefox than is on the Win 11 computer but was not the most recent version available.

Any ideas for installing the backup file or for a work around so I have my most recent profile data, bookmarks and passwords on the Win 11 computer?

I use Firefox under Fedora (I'm two OS versions behind, must upgrade soon). I open very many tabs each day then work through them, theoretically every day, in practice they accumulate and I deal with them when I can. I rely on the tabs loading correctly on restart, but today they didn't, instead the set of tabs that were opened a few days ago loaded, and I lost everything I had done since then. Is there a way to retrieve the tabs that were opened just before this happened, ie around 15-20 hours ago? Ideally, again, I would merge them with the current ones, but reopening the old ones would take much much longer than reopening the new ones. Thank you for any advice.

Firefox prompted me to update, I hit download, my entire PC froze, I restarted the computer, when I opened firefox again and hit "restore session" it restored a session that I had opened months ago. When I checked my history, everything after that older session had been deleted. All of my history from the past few months has been deleted. I tried a few different solutions from trying to research the problem, nothing so far has worked. The only thing I have found is a session restore error saying "could not decompress file", but I could not find the file it was attempting to decompress. This is the error message I found.

1785894397652 SessionStore ERROR NotReadableError when reading session file: recovery: NotReadableError: Could not read `C:\Users\ansen\AppData\Roaming\Mozilla\Firefox\Profiles\xpnhovd6.default-release\sessionstore-backups\recovery.jsonlz4': could not decompress file: invalid LZ4 header: wrong magic number: `00 00 00 00 00 00 00 00 00 00 00 00' (NS_ERROR_FILE_CORRUPTED) No traceback available 1785894397756 SessionStore ERROR NotReadableError when reading session file: recoveryBackup: NotReadableError: Could not read `C:\Users\ansen\AppData\Roaming\Mozilla\Firefox\Profiles\xpnhovd6.default-release\sessionstore-backups\recovery.baklz4': could not decompress file: invalid LZ4 header: wrong magic number: `00 00 00 00 00 00 00 00 00 00 00 00' (NS_ERROR_FILE_CORRUPTED) No traceback available

Any help is greatly appreciated. I'm one of those people that tends to have way too many tabs open at once due to poor memory, and losing months of tabs and progress is a huge setback. I'm very desperate to get the history and tabs back.

個人的にFirefoxの過去のアクセス履歴が欲しいため、毎日places.sqliteのバックアップを取得していました。 先日、バージョン154.0になった時点で、突然それまで利用していたアクセス履歴やブックマークが使えなくなり、バックアップしていたplaces.sqliteファイルをコピーしても同様の現象が起こってしまいます。

詳しく調べたところ、どうもバージョン154からplaces.sqliteに格納されているテーブルの構造が変わっているようで、アクセス履歴などが消えた理由もそこにありそうです。

今後も過去のアクセス履歴は利用したいため、直前のバージョンのplaces.sqliteを新しいバージョンに移行する具体的な方法について、もしご存じの方がいらっしゃったらご教示お願いします。 （sqlite managerなどツールを使ってのインポート／エクスポートは既に試しております）

Subject: Help recovering old Firefox Sync data using my Recovery Key

Hello Mozilla Support,

I’m trying to recover my old Firefox Sync data, especially my bookmarks and saved passwords.

I still have an Account Recovery Key that I saved on August 27, 2025. However, after signing in to my Mozilla account today, my account page shows “Account recovery key: Not set”, and syncing does not restore my old bookmarks or passwords.

I may have reset or changed my Mozilla account password today without using the old Recovery Key during the process.

Could you please confirm:

Is there any way to use my old Recovery Key now to recover the previously encrypted Firefox Sync data? Is the old Sync data still retained on Mozilla’s servers in any recoverable form? Is there any other recovery procedure available for bookmarks, passwords, or previous Sync data?

I still have access to the same Mozilla account and the original Recovery Key file. I will not send the Recovery Key itself unless there is an official secure procedure that requires it.

I recently got a new laptop. The FIREFOX app on my new laptop doesn't have File Edit View Bookmarks Profiles Tools and Help on the very top. I can't find my bookmarks with the folders I created.

My Firefox created a new profile and reset everything. I was able to go back and locate my bookmarks and restore them, but my menu bar is reset, my history and saved passwords etc are all gone.

Our power went out this am and turned off my computer. I am unable to recover my Firefox bookmarks. I've done the Manage bookmarks, but when I get to Library there is no Import/Backup to click on.

Firstly I have lost my default,. I had it set up as google . next I lost all my bookmarks, I have also lost the bar I had which included bookmarks history etc. this all happened in the middle of using a program and now I cannot get it back. PLEASE TELL ME WHAT IS HAPPENING

My FireFox was updated to version 153 and all of my bookmarks are gone. I tried to restore them in Manage Bookmarks. But when i click on 'Import and Backup', then 'Restore', then click on 'choose file' nothing happens. I navigated to the directory "bookmarkbackups" and I can see several backups, one dated 08/06/2026. But how do I get Manage Bookmarks to see that file?

I tried to bookmark a current tab and it does not show up under Bookmarks. why can't I set a new bookmark? Are these issues related?

I'm on Windows 10.

For the Troubleshooting data, I manually open about:support and clicked on 'Copy text to Clipboard'. Then pasted that into the box below.

I didn't know I need to keep a device on if I want to sync my old data. I read it thoroughly. This is annoying, I don't want to lose my Sync data from this because I didn't know. How do you guys retain your Sync data if I were to reset my password? My computer just got fixed and I don't like this greeting of where all my data like history and bookmarks flushed down because I wasn't signed-in in a device nor did I place a key or something.