Sorry to hear about the crash. Firefox should automatically restore the non-private windows on the next restart.

Could you check the menu. Are either of these available:

• "3-bar" menu button > History > Restore Previous Session
• (menu bar) History > Restore Previous Session

If they are missing or grayed, check either:

• "3-bar" menu button > History > Recently Closed Windows
• "Library" toolbar button > History > Recently Closed Windows
• (menu bar) History > Recently Closed Windows

Note: Each window also has its own Recently Closed Tabs list.

If you don't have anything to restore, I suggest looking to see whether Firefox is updating the session history files in real time. Here's how:

Open your profile folder using this page:

• "3-bar" menu button > Help > More Troubleshooting Information
• (menu bar) Help > More Troubleshooting Information
• type or paste about:support in the address bar and press Enter

In the first table on the page, find the Profile Folder row. On that row, click the "Open Folder" button. This should launch Windows' File Explorer listing the contents of your current profile folder.

In your profile folder, double-click into the sessionstore-backups folder. Change the view to show the modification date/time so you can keep an eye on those.

By default, Firefox updates the recovery.jsonlz4 file (and its backup, the recovery.baklz4 file) as often as every 15 seconds with your session changes, such as opening a new tab or moving to a new page within a tab.

Can you see these files updating as you browse, or are they missing or frozen in time?

While we work on diagnosing this problem, I will mention some session management add-ons that you could consider as a supplement to the built-in feature. These are the ones I'm aware of that you might investigate/try out:

Use database storage:

• https://addons.mozilla.org/firefox/addon/tab-session-manager/
• https://addons.mozilla.org/firefox/addon/session-boss/

Use bookmark storage:

• https://addons.mozilla.org/firefox/addon/session-sync/
• https://addons.mozilla.org/firefox/addon/my-sessions/

Bookmark storage is more robust in that Firefox backs it up regularly. However, having the extra data show up when you are searching your bookmarks may be annoying.

In the address bar, type about:crashes<enter>. Note: If any reports do not have BP- in front of the numbers/letters, click it to submit them.

The crash report is several pages of data. We need the report numbers to see the whole report.

Using your mouse, mark the most recent 7 - 10 Submitted crash reports, and copy them. Now go to the reply box and paste them in.

Please, Do not post a screenshot ! !

For more help on crash reports, see; https://support.mozilla.org/en-US/kb/firefox-crashes-asking-support

@jscher2000 no where, anywhere was the Restore Previous Session found. I looked before posting. Also, I tried several other tutorials on restoring from recovery.baklz4, and nothing. Did not restore.

@FredMcD I looked there and the last listed crash report was from October 3, 2021 and none of them have a B- before them. They all start with numbers. Nothing from 12/11/2021 which is really disappointing.

The fact that I have to add a third-party untrusted add-on to my browser to backup or sync my tabs is a shame. I work with confidential material, user logins and I cannot trust their information for product that are not developed by your company.

Use these links to create a new profile. Use this new profile as is. Is the problem still there?

https://support.mozilla.org/en-US/kb/how-run-firefox-when-profile-missing-inaccessible

http://kb.mozillazine.org/Profile_folder_-_Firefox#Navigating_to_the_profile_folder

https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles

https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles

Type about:profiles<enter> in the address bar.

@jscher2000 no where, anywhere was the Restore Previous Session found. I looked before posting.

The items will be missing or grayed out if Firefox already did the automatic restore. Next time check either:

• "3-bar" menu button > History > Recently Closed Windows
• "Library" toolbar button > History > Recently Closed Windows
• (menu bar) History > Recently Closed Windows

Also, I tried several other tutorials on restoring from recovery.baklz4, and nothing. Did not restore.

If you were using one of mine, you would have made backups of your older recovery.jsonlz4/.baklz4, previous.jsonlz4, and upgrade files. Do you still have those?

@FredMcD I looked there and the last listed crash report was from October 3, 2021 and none of them have a B- before them. They all start with numbers. Nothing from 12/11/2021 which is really disappointing.

Are you sure Firefox is crashing? Do you get a dialog from either Firefox or Windows saying that Firefox crashed? Or is Firefox just closing without any dialog?

The fact that I have to add a third-party untrusted add-on to my browser to backup or sync my tabs is a shame. I work with confidential material, user logins and I cannot trust their information for product that are not developed by your company.

Don't install any software you don't trust.