Hi KELev, I'm sorry to hear about your data loss.

If Firefox did not restore your session automatically, could you check whether the option is available from the menu? Either:

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

If those items are missing or grayed, could you check for closed windows in either of these places, in case the session was restored but with a closed status for your real window(s):

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

If you find nothing there, hmm, why didn't Firefox find your tabs? We should check your privacy settings on the Options page:

• Windows: "3-bar" menu button (or Tools menu) > Options
• Mac: "3-bar" menu button (or Firefox menu) > Preferences
• Linux: "3-bar" menu button (or Edit menu) > Preferences
• Any system: type or paste about:preferences into the address bar and press Enter/Return to load it

In the left column, click Privacy & Security

Automatic Private Browsing?

On the right side, in the History section, either of these will trigger automatic private browsing, so no history is retained when Firefox is closed:

• "Firefox will: Never remember history"
• "Firefox will: Use custom settings for history" + "Always use private browsing mode"

If you have either of those set, change to "Firefox will: Remember history" or uncheck the box for "Always use private browsing mode".

Clearing history at shutdown?"

Select: Firefox will: Use custom settings for history so you can view the detailed settings. Then check this setting:

• "Clear history when Firefox closes" -- not checked, ok

• "Clear history when Firefox closes" -- checked => click the Settings button and make sure "Browsing & Download History" is NOT set to be cleared

Did you make any changes? If so, does that help?

As a possible workaround:

When installing an update, Firefox should create a snapshot of your session at that time. You could find that file and convert it to a clickable list of links to the pages you had open. Here's how:

(1) To open your profile folder...

If Firefox is still running:

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 Folder" (or "Show in Finder") button.

If Firefox is closed:

Type or paste the following into the Windows Run dialog or the system search box and press Enter to launch Windows Explorer:

%APPDATA%\Mozilla\Firefox\Profiles

In that folder, do you see a semi-randomly-named folder? If so, click into it. If you find multiple such folders, find the one that was most recently updated.

(2) Copy out session history files

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

(3) 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

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.

Restore was grayed out in step one (it didn't used to be until this upgrade} In library, history now only showed one window from this evening. In Privacy and Security, it is set for Firefox will remember history...

So there were no changes to be made. Thanks for trying.

Were you able to find any relevant files in the sessionstore-backups folder?

If not, do you have a new Old Firefox Data folder on your desktop from a Firefox Refresh?

jscher2000 said

As a possible workaround: When installing an update, Firefox should create a snapshot of your session at that time. You could find that file and convert it to a clickable list of links to the pages you had open. Here's how: (1) To open your profile folder... If Firefox is still running: 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 Folder" (or "Show in Finder") button. If Firefox is closed: Type or paste the following into the Windows Run dialog or the system search box and press Enter to launch Windows Explorer: %APPDATA%\Mozilla\Firefox\Profiles In that folder, do you see a semi-randomly-named folder? If so, click into it. If you find multiple such folders, find the one that was most recently updated. (2) Copy out session history files In your profile folder, double-click into the sessionstore-backups folder. Save all files here to a safe location such as your Documents folder. (3) 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

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. </blockquoteI <p>

I don't see how to move the upgrade.json.....file to your page...when I am under the troubleshooting page I can't see the other open tabs. There are no headings there for recovery. Some say previous. But the dates are all from yesterday when none of my prior tabs had been saved from history.

jscher2000 said

Were you able to find any relevant files in the sessionstore-backups folder? If not, do you have a new Old Firefox Data folder on your desktop from a Firefox Refresh?

The session store didn't work. I can't see the tab with your page to drag and drop it onto when I have jTroubleshooting open.

I don't see anything labeled "old Firefox Data" on my desktop. The Firefox that is now running is version 64.

I can see history of browsing though. I can go through and hand select the tabs that were open, I think. I am so disappointed because I leave a few pages open on online classes, emails, etc that I don't want to forget about. I had the option marked to always restore session on opening Firefox.

Thanks for your help.

Ok I found a way to drag and drop the Upgrade.jsonlz4 file to your page.

All it had was "open windows" title not available Welcome back..

?

KELev said

The session store didn't work. I can't see the tab with your page to drag and drop it onto when I have jTroubleshooting open.

Hmm, you should be able to resize the Windows Explorer window listing your session history files so you can see Firefox behind it. But yes, you need to load the Scrounger in a visible tab so you can drop files onto it.

Alternately, if you backed up your session history files to an easy-to-find location, you could use the Browse button on the Scrounger page to load a file. (This is a huge pain if you have to dig down into your normal profile folder.)

Did you verify that you do not use "Clear history when Firefox closes" to clear the browsing history?

KELev said

Ok I found a way to drag and drop the Upgrade.jsonlz4 file to your page.
All it had was "open windows" title not available Welcome back..

It sounds as though that file is too new. Here are some other things to check:

(A) Do you have any recent backups of your current sessionstore-backups folder?

It's possible Windows took a snapshot during a system update. Don't use system restore! That typically causes more problems.

There are several programs you can use to export files from restore points. Here's the rundown:

(1) Set Windows to show hidden files and folders:

https://support.microsoft.com/en-us/help/14201/windows-show-hidden-files

(2) Download and run one of these programs:

• ShadowExplorer: http://www.shadowexplorer.com/
• System Restore Explorer: http://nicbedford.co.uk/software/systemrestoreexplorer/

Within the most recent restore point shown in the program, you can explore along this path to see whether you can find a timely shadow copy of your profile:

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

(3) Within your profile folder, check the sessionstore-backups folder for any useful looking files and Export them to a safe location.

Then you can scrounge them to see whether they have what you need.

(B) Do you have any other profile folders?

(1) Does the Profile Manager list other profile folders?

To check on that, inside Firefox, type or paste about:profiles in the address bar and press Enter/Return to load it.

This page should list all the profiles Firefox is currently aware of. If you see a profile that is not currently set as default that looks promising, scroll down to it and click the Set as default profile button below that profile, then scroll back up and click the Restart normally button. (There are some other buttons, but I think those are still "under construction" so please ignore them.)

Firefox should exit and then start up using the other profile. Is that the right one?

If there's nothing there:

(3) Did Firefox orphan your old profile folder?

Here's how to check whether there are additional profile folders in the standard location in addition to the one you're using. Start by opening your current 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/Return

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

In the Windows Explorer address bar, click the capitalized word Profiles to move up one level in the folder hierarchy. More than one folder here by any chance? Do the files in those folders look like they were last updated around the time of the update?

If you've got any promising looking folders, you can check the sessionstore-backups folder to see the dates on the files there. Anything look useful?