This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Rohkem teavet

How to (force?) load a backup version of session file due to clean start after Firefox crash?

  • 4 vastust
  • 1 on selline probleem
  • 1 view
  • Viimati vastas cor-el

more options

Hello. I can't restore session from backup using advices which were provided in another answers on this forum.

Steps to reproduce:

- open a lot of tabs
- Firefox has been crashed (well, I had to use `kill -15 PID' actually, since it has been frozen first)
- note that sessionstore.jsonlz4 doesn't exist anymore in profile directory, so current session has been wiped away completely
- start Firefox
- see a new clean session and note, that "..." menu > "Restore Previous Session" is grayed out
- close Firefox
- find the latest (by time) session backup file in your profile directory: mine is sessionstore-backups/recovery.jsonlz4
- use it as a new current session file (e.g., shell command from profile directory): cp sessionstore-backups/recovery.jsonlz4  sessionstore.jsonlz4
- start Firefox again

What should happen:

- Firefox should restore session from a "new" sessionstore.jsonlz4 backup file OR make "Restore Previous Session" option is available

What happens:

- clean session again
- "Restore Previous Session" is not available
- try another session backup files: same results

What am I doing wrong?

Thanks in advance.

P.S. Yes, I know that I can use https://www.jeffersonscher.com/res/scrounger.html * to get links from session file and manually restore my session, but shouldn't Firefox do it automagically for me? Is there any extension, so I can 'force' Firefox to load session from backup file? Now, when Firefox starts, looks like it's just can't "see" sessionstore.jsonlz4 file.

Hello. I can't restore session from backup using advices which were provided in another answers on this forum. Steps to reproduce: - open a lot of tabs - Firefox has been crashed (well, I had to use `kill -15 PID' actually, since it has been frozen first) - note that sessionstore.jsonlz4 doesn't exist anymore in profile directory, so current session has been wiped away completely - start Firefox - see a new clean session and note, that "..." menu > "Restore Previous Session" is grayed out - close Firefox - find the latest (by time) session backup file in your profile directory: mine is sessionstore-backups/recovery.jsonlz4 - use it as a new current session file (e.g., shell command from profile directory): cp sessionstore-backups/recovery.jsonlz4 sessionstore.jsonlz4 - start Firefox again What should happen: - Firefox should restore session from a "new" sessionstore.jsonlz4 backup file OR make "Restore Previous Session" option is available What happens: - clean session again - "Restore Previous Session" is not available - try another session backup files: same results What am I doing wrong? Thanks in advance. P.S. Yes, I know that I can use https://www.jeffersonscher.com/res/scrounger.html * to get links from session file and manually restore my session, but shouldn't Firefox do it automagically for me? Is there any extension, so I can 'force' Firefox to load session from backup file? Now, when Firefox starts, looks like it's just can't "see" sessionstore.jsonlz4 file. *Note: since I've got ~6.7MB session file, I get browser freezes using JS version, so I prefer this standalone local tool - https://github.com/avih/dejsonlz4

All Replies (4)

more options

If there is no session save or none showing you can't update something that isn't there.

more options

Separate Issue; Your System Details shows;

Installed Plug-ins

Shockwave Flash 28.0 r0 Shockwave Flash 27.0 r0
Having more than one version of a program may cause issues. You must remove the older programs. Then get the current full installer.

Flash: Grab the uninstaller from here:

http://helpx.adobe.com/flash-player/kb/uninstall-flash-player-windows.html Uninstall Flash Player | Windows

http://helpx.adobe.com/flash-player/kb/uninstall-flash-player-mac-os.html Uninstall Flash Player | Mac

Then reinstall the latest version.

Note: Windows users should download the active_x for Internet Explorer. and the plugin for Plugin-based browsers (like Firefox).

Note: Windows 8 and Windows 10 have built-in flash players and Adobe will cause a conflict. Install the plugin only. Not the active_x.

Flash Player Version 28.0.0.137

https://get.adobe.com/flashplayer/ Direct link scans current system and browser Note: Other software is offered in the download. <Windows Only>

https://get.adobe.com/flashplayer/otherversions/ Step 1: Select Operating System Step 2: Select A Version (Firefox, Win IE . . . .) Note: Other software is offered in the download. <Windows Only>


See if there are updates for your graphics drivers https://support.mozilla.org/en-US/kb/upgrade-graphics-drivers-use-hardware-acceleration

more options

WestEnd said

If there is no session save or none showing you can't update something that isn't there.

Yes, there are a few valid jsonlz4 session files. They can be "unpacked" by mentioned lz4 tool. I can see session information (windows/tabs with links) inside these unpacked regular js files. But they can't be loaded by Firefox automatically (as it should) - that's a problem.

So I just would like to know (as one of possible solution): maybe is there any way to force Firefox use particular session file on start since simple file replacement don't do the trick?

Thank you for your respond.

more options

I'm not sure if Firefox tries to restore a session from files in the sessionstore-backups folder when you kill Firefox. I think that this should work in most cases and you get presented with the about:sessionrestore page. A sessionstore.jsonlz4 file only gets created when Firefox closes properly, otherwise there are only the files in the sessionstore-backups folder.

You can set this pref to 0 on the about:config page to get the about:sessionrestore page immediately with the first start after a crash has occurred or the Task Manager was used to close Firefox.

  • browser.sessionstore.max_resumed_crashes = 0