Closed 8 windows, could only restore 3 - need to restore the other 5 (Win10)
Within the last hour or so, I needed to close Firefox while installing an app (the setup was recommending to close all Windows programs).
Had 8 windows open.
Right-clicked on the Taskbar Firefox icon, then selected the option "close all windows" - it proceeds to close each window consecutively, asking me each time for manual confirmation whether to close this window with x tabs in it - and I just confirm each time.
So then after that setup is completed, I open Firefox again - the last closed window is restored (as per the settings);
then I click on History, "recently closed windows", and.... there's only 2 windows on that list. I restore those 2, and then the list is empty - nothing more to restore.
So if I had restarted the PC, it would've just restored the 8 windows upon reopening Firefox, as usual - but since I opted to just close Firefox like this, "close all windows", I just lost 5 windows.
So could anything be done here?
Something in the files? Maybe the C:\Users[user]\AppData\Roaming\Mozilla\Firefox\Profiles\4qu1kfr9.default-release\sessionstore-backups path? There's a file called "previous.jsonlz4" in there, something I could do with that one?
Or something else?
Any help would be appreciated!
All Replies (9)
Like you noticed, only three closed windows can be restored as set via the undo prefs on the about:config page.
- browser.sessionstore.max_windows_undo
- browser.sessionstore.max_tabs_undo
You should have closed Firefox via Exit/Quit to close all windows at once instead of individually closing all windows. Usually the only option is to restore a recent upgrade file in the sessionstore-backups folder as all other files likely have been replaced since you have opened Firefox.
You will normally find these files in the sessionstore-backups folder:
- previous.jsonlz4 (cleanBackup: copy of sessionstore.jsonlz4 from previous session that was loaded successfully)
- recovery.jsonlz4 (latest version of sessionstore.jsonlz4 written during runtime)
- recovery.baklz4 (previous version of sessionstore.jsonlz4 written during runtime)
- upgrade.jsonlz4-<build_id> (backup created during an upgrade of Firefox)
You can copy a file from the sessionstore-backups folder to the main profile and rename the file to sessionstore.jsonlz4 to replace the current file with Firefox closed.
- make sure to backup the current sessionstore.jsonlz4
You can look at this tool to inspect a compressed jsonlz4 sessionstore file. This tool works locally, no uploading done.
Hm I can't seem to find the "sessionstore.jsonlz4" file, is it hidden? Is it supposed to be in the Firefox\Profiles folder?
"previous.jsonlz4 (cleanBackup: copy of sessionstore.jsonlz4 from previous session that was loaded successfully)"
Does that mean the previous session in the state it was loaded upon reopening Firefox the previous time? I.e. with none of the changes made to the session between that point and the shutdown yesterday?
And "recovery.baklz4 (previous version of sessionstore.jsonlz4 written during runtime) " means it's the previous session in its latest form, right before said shutdown?
So in this case presumably only containing the last closed window which was then restored upon reopening this current session?
Modified by fbacount
Ok looked again, I've got a "previous.jsonlz4" and "upgrade.jsonlz4-<build_id>" both of the same size and "last modified" at the same point in time (yesterday around the time of closing I think).
Meanwhile "recovery.jsonlz4" and "recovery.baklz4" are also of the same size (between one another) and are being modified continuously.
Modified by fbacount
(And additional short-term question:)
I've made a copy of the entire "Profiles" folder, incl. the "sessions-backups" folder - does that mean I can now safely restart the PC / Firefox without any further data loss or making the recovery of these lost windows any more difficult? I.e. there's nothing outside the Profiles folder that also needs to be saved before it then gets overwritten upon restart?
_______________________
And also - increasing the number of "browser.sessionstore.max_windows_undo" on about:config isn't gonna do anything for those lost windows, right?
Modified by fbacount
Yes, this only works for the current session and future sessions, you can't recover windows closed in the past. If you want to cleanup these lists then you can temporarily set an undo pref to '0'.
Ah, oh well, I see.
Asked BAIChat about whether "anything outside "\Profiles"" had to be copied in this kind of situation, and got the answer that definitely no, everything relevant to previous session storage is already contained in that folder (and "sessionstore-backups" in particular). So I suppose nothing to worry about there - unless those AI chatbots incl. this one are unreliable incl. in this area?
And aside from that, still haven't managed to figure out where the"sessionstore.jsonlz4" file is - whether it's hidden, and what folders it's in etc. - especially since I need to back it up before replacing it with "previous.jsonlz4" or the latest "upgrade.jsonlz4-<build_id>" file?
The sessionstore.jsonlz4 file is only present when Firefox is closed. When Firefox is running then files in the sessionstore-backups folder are used.
You will normally find these files in the sessionstore-backups folder:
- previous.jsonlz4 (cleanBackup: copy of sessionstore.jsonlz4 from previous session that was loaded successfully)
- recovery.jsonlz4 (latest version of sessionstore.jsonlz4 written during runtime)
- recovery.baklz4 (previous version of sessionstore.jsonlz4 written during runtime)
- upgrade.jsonlz4-<build_id> (backup created during an upgrade of Firefox)
You can copy a file from the sessionstore-backups folder to the main profile and rename the file to sessionstore.jsonlz4 to replace the current file with Firefox closed.
- make sure to backup the current sessionstore.jsonlz4
You can look at this tool to inspect a compressed jsonlz4 sessionstore file. This tool works locally, no uploading done.
cor-el said
The sessionstore.jsonlz4 file is only present when Firefox is closed. When Firefox is running then files in the sessionstore-backups folder are used.
Ah, closed it and found it now, ok.
You will normally find these files in the sessionstore-backups folder:Wonder if there's a difference between those two, i.e. in terms of replacing sessionstore.jsonlz4 with it? When they're of the same session and have the same size and last modification time? I used this on both:[...]
- previous.jsonlz4 (cleanBackup: copy of sessionstore.jsonlz4 from previous session that was loaded successfully)
You can copy a file from the sessionstore-backups folder to the main profile and rename the file to sessionstore.jsonlz4 to replace the current file with Firefox closed.
- upgrade.jsonlz4-<build_id> (backup created during an upgrade of Firefox)
- make sure to backup the current sessionstore.jsonlz4
You can look at this tool to inspect a compressed jsonlz4 sessionstore file. This tool works locally, no uploading done.
and they seem identical, however the tool seems buggy and only works with the "unstructured URL list" - and in a few cases doing as much as maximizing and de-maximizing the browser window froze the page and required a reload - and the "upgrades" one seemed to be more susceptible to that, after several attempts.
Could that be a problem with the tool, or does that mean the session files have some kinda problem?
Oh, sorry - is there any additional available information about those latest questions?