Sorry to hear about these unexpected data losses.

Regarding cookies, Firefox doesn't keep a backup of the cookies.sqlite database, but Windows might have captured a snapshot of it when you did your last round of "patch Tuesday" updates. To check for that:

First, make sure Windows is set to show hidden files and folders: https://support.microsoft.com/en-us/help/14201/windows-show-hidden-files

Next, try one of these programs:

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

Within each restore point you check, you can explore along this path to a file you might swap in:

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

Regarding pinned tabs, I think if you are not using the container tabs extension, they are stored with regular session history. Do you need the list of what they were? You could try this:

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

• "3-bar" menu button > "?" button > 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.

In your profile folder, scroll down and double-click into the sessionstore-backups folder. I suggest saving all files here to a safe location.

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

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/res/scrounger.html

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

Well, the scrounger doesn't really work, since it says Invalid Date for the last modified date, and doesn't show any windows and tabs (even for current files, that definitely have open tabs). (EDIT: whatever you did fixed this)

If going to the Previous Versions tab of the Properties of my cookies.sqlite files shows nothing, that means I'm out of luck, right? I'm on a work computer, so can't install weird tools like those you linked to.

Why did Firefox feel like it needed to update to non-beta, and then the very next time I went to About Firefox, it wanted to update back to the beta channel (specifically to 59.0b3).

Narvey said

Well, the scrounger doesn't really work, since it says Invalid Date for the last modified date, and doesn't show any windows and tabs (even for current files, that definitely have open tabs).

I haven't heard of an Invalid Date error. What is the actual last modified date for the file? Maybe Firefox -- or at least my script -- is not able to read the file for some reason such as lack of permissions. Permissions issues will definitely cause data access problems for Firefox.

If going to the Previous Versions tab of the Properties of my cookies.sqlite files shows nothing, that means I'm out of luck, right? I'm on a work computer, so can't install weird tools like those you linked to.

Windows 10 doesn't have the same kind of Previous Versions tab as Windows 7 did. I think it normally only works with the optional File History feature.

One possible workaround from the Windows 8 days is to do this hacky thing:

(A) Open your Firefox profile folder (B) Click in the address bar so you can see the entire path (C) Replace C: with \\localhost\c$ and then press enter to reload the folder that way

Then check for Previous Versions to see if Restore Points show up.

By the way, did Firefox create a file named cookies.sqlite.corrupt (or similar)?

Why did Firefox feel like it needed to update to non-beta, and then the very next time I went to About Firefox, it wanted to update back to the beta channel (specifically to 59.0b3).

I suspect what happened is that your Firefox 58 beta was updated to a Firefox 58 release candidate. Those are not specifically labeled as beta or release: if they test out, they become the release, if they do not test out, they are replaced by a different release candidate. But you never actually left the beta channel.

jscher2000 said

Narvey said

Well, the scrounger doesn't really work, since it says Invalid Date for the last modified date, and doesn't show any windows and tabs (even for current files, that definitely have open tabs).

I haven't heard of an Invalid Date error. What is the actual last modified date for the file? Maybe Firefox -- or at least my script -- is not able to read the file for some reason such as lack of permissions. Permissions issues will definitely cause data access problems for Firefox.

You also could try running the Scrounger in Microsoft Edge or Google Chrome to see whether it can open/read the file. (I've never tested Edge for this.)

"Invalid Date" is probably about an error in the file with a date field that can't be converted. Maybe use try and catch blocks in the script to detect such errors or add "|| <some date>;" as a fallback.

jscher2000, whatever you did to the scrounger fixed it. Do you know the people who own https://firefox-session-restore.herokuapp.com/? they might need to update it as well.

(Also, I still wasn't able to find restore points, but that's OK, I've re-logged in to all the sites I need to now).

OK, next time I restarted Firefox the problem cropped up again, and the "Show your windows and tabs from last time" setting stopped working (it would show homepage instead, not sure why).

Fixed it by backing up my profile, refreshing firefox (ouch), and then copying my extensions and browser-extension-data folders from the old profile to the new one.