So you have tabs with only the last active page showing, or you have a set of blank tabs?

Firefox creates numerous session history files, but because session history is only for the immediately previous session, it is unfortunately too easy to lose it. Could you start by making a backup of your existing session history files? Here's how:

You can open your current Firefox settings (AKA Firefox profile) folder using either

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

In the first table on the page, click the "Open Directory" (or "Open Folder" or "Show in Finder") button.

I don't know what you'll see on Linux. Do you see a folder here named sessionstore-backups? If not, you probably see one or more folders with a partially random name, like a1b2c3d4.default -- click into the one that seems most recently updated.

In your profile folder, double-click into the sessionstore-backups folder. Save all files here to a safe location such as your Documents folder.

What files did you find?

The kinds of files you may find among your sessionstore files are:

• recovery.jsonlz4: the windows and tabs in your currently live Firefox session (or, if Firefox crashed at the last shutdown and is still closed, your last session)
• recovery.baklz4: a backup copy of recovery.jsonlz4
• previous.jsonlz4: the windows and tabs in your last Firefox session
• upgrade.jsonlz4-build_id: the windows and tabs in the Firefox session that was live at the time of your last update
• various .js files from Firefox 55 or earlier

Could you take a look at what you have and the date/time of the various files to see whether you think any of them would have the missing tabs?

To preview the contents of a file, you can drag and drop it onto this page, then click Scrounge URLs: https://www.jeffersonscher.com/ffu/scrounger.html

That tool is on my site, so please let me know if it doesn't work for you.

Thank you for your response.

"So you have tabs with only the last active page showing, or you have a set of blank tabs?"

Actually, I have many tabs where the only thing is a URL in the address bar. What makes it worse and more work is that one must put the cursor in the address line and then press Enter to get that page to load. Otherwise, it will not and the page stays blank.

"Firefox creates numerous session history files, but because session history is only for the immediately previous session......"

What do you mean by "immediate previous session""?

BoyNamedSue said

What do you mean by "immediate previous session""?

The session before the current one.

Usually when you activate a restored tab, Firefox will load a cached version of the page. I don't know why that isn't happening with your restored session. It's good to hear that the URLs are present and not lost.

Well, I have not found a way to restore anything because that function appears to be missing in the latest version.

Also, keep in mind that listed URLs are the only ones and there is no history before the displayed one.

If you already checked the folder I mentioned before, two other places to look for old session history files would be:

• Other profile folders that could exist under:
  ~/.mozilla/firefox/

• A folder inside an Old Firefox Data folder created on your desktop (does Linux have a desktop?) by the Refresh feature

Yeah, I appreciate all the ideas you offered. I just don't feel a user should have to jump thru hoops. Maybe that's just me. I have always set my browser to restore all tabs from last time, and it is still that way.

It used to be that the system worked differently. So what bothers me is: A: Why was a change necessary? B: Why wasn't the user notified in advance of messing up one's productivity: C: What happened to the session manager?

I've used Firefox's built-in automatic session restore (option to restore previous session windows and tabs on the Preferences page) for several years without a hitch, except one time when luckily it worked on the second startup.

Were you using the Session Manager extension rather than the built-in feature? Session Manager isn't compatible with Quantum versions of Firefox. If you want to try to restore a session saved by Session Manager, here's how, and yes, it is more work:

(A) Convert Session Manager file to a Firefox JSON session file

In your profile folder, there is a directory named sessions that contains your Session Manager files.

Use this tool to save one off as a JSON file: https://www.jeffersonscher.com/ffu/scrounger.html

(B) Swap the JSON file for your current session

To try swapping in an older session history file so Firefox will load it, the standard "manual swap" method is as follows (assuming Firefox is still running):

(1) From inside Firefox, open your current Firefox settings (AKA Firefox profile) folder using either

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

In the first table on the page, click the "Open Folder" button. This should launch a Windows Explorer window listing the various files and folders in your profile.

(2) Leaving that window open, switch back to Firefox and Exit, either:

• "3-bar" menu button > "power" button Exit
• (menu bar) File > Exit

Pause while Firefox finishes its cleanup -- a file named sessionstore.jsonlz4 should appear in the folder.

(3) Once Firefox has stopped updating things, while viewing the main level of the profile folder, right-click > Rename sessionstore.jsonlz4 to sessionstoreOLD.jsonlz4

If you see an older sessionstore.js or sessionstore.bak file, move it somewhere else or delete it.

(4) Copy in the other file you want to restore, and rename it with the name appropriate for its format:

• Compressed file such as recovery.jsonlz4 => sessionstore.jsonlz4
• Uncompressed file such as recovery.js => sessionstore.js

(5) Hide the sessionstore-backups folder by renaming it to sessionstore-backupsOLD. This is a precaution when you are using an uncompressed file to Firefox doesn't preferentially use the previous.jsonlz4 file in that folder.

(6) Start Firefox and it should read the swapped in sessionstore file and restore whatever was in the substitute file; if you do not have Firefox set to restore your previous windows and tabs automatically, use History > Restore Previous Session

Any luck?

I just looked at the legacy add-ons that were disabled and Session Manager was one of them. That must be what happened.

The sad thing is that ESR was not supposed to have that problem. That's the whole point in using ESR.

Damn!

The point of ESR is that you only get major feature changes about once a year, with security updates in between, so you can maintain stability for a longer period of time... but not forever. https://www.mozilla.org/firefox/organizations/faq/

Try the Firefox version from the official Mozilla server if you currently use a version from the repositories of your Linux distribution.

• https://www.mozilla.org/en-US/firefox/organizations/all/
• https://www.mozilla.org/en-US/firefox/all/

The situation the users are left in is all very sad. Oh well, that's probably why people stop making monetary contributions to software development. There is no common sense left in software design. Bad leadership and no explanations.

I guess I just have to find add-on replacements.

Thanks, all.

If you want to use an add-on to manage your sessions, you have several choices. https://addons.mozilla.org/firefox/extensions/