aceexploration, sorry that you lost your tabs. The Forget panel states that it will close all tabs and windows, as well as deleting recent cookies and history. It also states that this action cannot be undone.

If you would prefer the Forget function to also only close recent tabs / windows instead of all of them, then you can make this request at: https://connect.mozilla.org/

Or if you feel that the wording could have been clearer, then you can also leave that feedback.

Hopefully someone knows of a way to recover a previous session? Maybe via the files in the sessionstore-backups folder within the profile folder?

You may wish to make backup copies of these files in the meantime, before closing Firefox?

If you do not know where your Profile folder is, see here: https://support.mozilla.org/en-US/kb/profiles-where-firefox-stores-user-data

You should have used "Clear Recent History" to clear recent history.

• https://support.mozilla.org/en-US/kb/delete-browsing-search-download-history-firefox

Using the Forget (panic) button will always close all open tabs and windows and open a new window, the range selection only applies to recent history and recent cookies.

• https://support.mozilla.org/en-US/kb/delete-browsing-search-download-history-firefox

Proceeding will:
 Close all Tabs and Windows
 Delete Recent Cookies
 Delete Recent History
 Open a new clean Window

You can check if you still have data in the sessionstore-backups folder.

• https://support.mozilla.org/en-US/kb/profiles-where-firefox-stores-user-data

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> (backups created during a Firefox update)

You can copy a file with Firefox closed from the sessionstore-backups folder to the main profile folder and rename the file to sessionstore.jsonlz4 to replace the current file.

• 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 is done.

• https://www.jeffersonscher.com/res/scrounger.html

Thank you for your belated news about deleting 'recent' history. But I am sorry, but I cannot check the problem as solved. That would only lure other users into this disastrous trap. The trap is still there. Unfixable, apparently:

As I read it now: the FORGET button, marked in the increments of time for which one's data will be forgotten [one might have supposed], does not forget the designated time increments only. It also closes [read 'deletes] everything. Although some might remain buried in "history". Or not.

Had I read about this button's function first, I would have read: Proceeding will:

Close all Tabs and Windows
Delete Recent Cookies
Delete Recent History
Open a new clean Window

Please note- that description tells me recent cookies and recent history will be deleted. And it also tells me all tabs will be closed. It specifically does not tell me all tabs will be deleted.

If it is truly a "panic" button, as mentioned above- one is likely to presume that the forget button set to 2 hours will actually forget only the last 2 hours.

If I wanted to delete the last full session, I could think of half a dozen ways to do that- including just turn off 'session restore' and restart the computer- and/or delete all profiles. And press "delete all history" under the history button. Deleting a session is easy.

But one might want an addon that will delete only designated history. FireFox users should be alerted to this : FORGET deletes ALL. Apparently, what "FORGET" means, it that one need FORGET the time increments the button lists. Instead, realize that ALL will be gone.

Deleting a short time within a session? -ah- use the forget button for 5 minutes. But the forget button set to 5 minutes- or set to 2 hoours- or set to one day: Doesn't matter how the Forget button is set- it will destroy ALL. Everything. [But also it deletes the last 5 minutes, so i guess you could say it worked].

What is the difference between a FORGET button that will remove ALL and a button that is labeled "REMOVE"? A FORGET button, one might have thought- helps one avoid removing [deleting, by default] everything

So I will spend today going thru all history of the last month in attempt to resurrect whatever I can find I have already checked Profiles, of course- did that last night, first thing.

But- the information about forget was out there. Had I paused to read below what i did read. Onus is on me.

USER BEWARE [or, use a different browser: except that until this happened, I had thought- and still do- that FireFox is the best browser of all:

I wonder.... Might there be a way FireFox could be made even better? A change that might prevent the hapless user from a seductive button that will causes loss of everything?? Am i really the only one who has wrongly viewed "Forget" button as a Forget button?

Just forget about the Forget button and if you have it in the Navigation Toolbar then remove it immediately as this is a dangerous button that never should be used by normal users. Just use other means to remove recent history like I posted above.

Do you still see files in the sessionstore-backups folder like I posted above.

You can use the button in "Help -> More Troubleshooting Information" (about:support) to go to the current Firefox profile folder or use the about:profiles page (Root directory).

• Help -> More Troubleshooting Information -> Profile Folder/Directory:
  Windows: Open Folder; Linux: Open Directory; Mac: Show in Finder
• https://support.mozilla.org/en-US/kb/profiles-where-firefox-stores-user-data

aceexploration, The Forget function did what it said it would do on its choices panel. It closed all tabs and windows. It removed recent cookies and history. It did this in such a way that this couldn't be undone.

If all tabs were closed but it was possible to undo this then someone could just perform the undo and then they would see what sites you were on. That is not "forgetting" your recent activity.

The other option would of course be to only close and forget "recent" tabs, but that might be problematic also.

Would this close newly opened tabs but leave older tabs? You might have opened a tab yesterday then navigated to a new site within it one minute ago, but that site would stay.

Or does it close any tabs that are new or that have recently changed? You would still lose an older tab if you had recently refreshed it. For example, you had an e-mail site open and checked for new messages one minute ago.

Or instead are tabs closed only if either they are new, or if a new site was opened within them? But now some users might expect an older site that was just refreshed to also be closed in order to forget this recent activity. But the site would stay along with its new content since the site itself is older.

At least with the nuclear option there is no scope for individual users complaining that they expected an open site to disappear, but it didn't because of it not meeting criteria that the user might not be stopping to think about when they just want to quickly "forget" recent activity.

It seems to me that the best they can do here is especially emphasise the part about all tabs and windows being closed and forgotten by this process, with the time range only applying to the other items. Again, not sure what they could or should do differently in terms of the Forget functions actions.

Windows will take a snapshot of your Firefox data folder when it does updates. So you may be able to find a shadow copy that is a week or two or three old, which might be better than nothing. Here's how:

(1) Set Windows to show hidden files and folders, if you haven't done this before:

https://support.microsoft.com/en-us/windows/view-hidden-files-and-folders-in-windows-97fbc472-c603-9d90-91d0-1166d1d9f4b5

(2) Download and install one of the following programs:

• ShadowExplorer: http://www.shadowexplorer.com/
• Shadow Copy View: https://www.nirsoft.net/utils/shadow_copy_view.html

(3) Start up the program and look for the latest restore point. Then explore along this path to see whether you can find a shadow copy of your profile:

\Users\your-user-name\AppData\Roaming\Mozilla\Firefox\Profiles\your.profile

(4) Check for a sessionstore.jsonlz4 file, and any potentially useful files in the sessionstore-backups folder and export them out to your live Windows desktop (not the desktop folder in the restore point)

Anything to work with there?

If you don't want to roll back to that date, I have a tool to dump out the list of tabs as a web page of clickable links. Either:

• https://www.jeffersonscher.com/ffu/scrounger.html
• https://jscher2000.github.io/Firefox-File-Utilities/scrounger.html (updated test version)