App tabs and Tab Groups (Panorama) are stored as part of the session data in the file sessionstore.js in the Firefox Profile Folder

• http://kb.mozillazine.org/Session_Restore

Make sure that you do not use Delete browsing, search and download history on Firefox to clear the "Browsing History"

Hi, To save your App tabs on Firefox, Try:

Open the Preferences window

• Select the General tab

Under Startup, click the drop down menu option for When Firefox starts.

Select and click: Show my windows and tabs from the last times

Next

• Select the Privacy tab

Under History, click the drop down menu option for Firefox will.

Select and click: Remember history

• Close the Preference window and restart Firefox.

Let us know how this work out for you.

I thought SalemRoger's suggestion was the solution.

Now, I find it doesn't always work. I followed his instructions exactly, but when I opened my computer today and went into Firefox, all my App Tabs were gone.

Back to the drawing board.

Hi SalemRoger,

This solution is valid for Tab Groups (Panorama)?

Yes, it works for Panorama!

Thank you SalemRoger.

Salem's solution kinda works. But i only want to save the app tabs not the other regular tabs. Is there such a way ?

The problem here is not just the app tab itself, but the help guide actually lies: http://support.mozilla.com/en-US/kb/what-are-app-tabs

It actually states, "All of the App Tabs you have set when you close Firefox will open as App Tabs when you start Firefox again."

It doesn't state, "All of the App Tabs you have set when you close Firefox will open as App Tabs when you start Firefox again IF you do this and you do that and you reset this..."

I can't believe this ever got past beta. Clearly this "feature" is no feature at all. The idea is a good one, but it doesn't work. We'd be better off with an extension that will do it for us.

I agree. Great idea but not ready for release. I'll make good use of it when it works as advertised and persists while still regularly clearing out history, etc.

A friend of mine had this same problem on Windows 7 that only happened when restarting the computer (not just Firefox itself) and after a bit of troubleshooting, we both concluded that this was because Windows prompts you to force close applications if they're prompting you for anything before closing.

In this case, it was Notepad that popped up and asked "Do you want to save the changes made to file foo.txt?" In Win 7, it only takes about 4-5 seconds before the task manager pops up in front of Notepad's (legitimate) dialog and instead prompts you to force close and restart the computer. If you do that, Windows 7 sends a different type of restart signal to applications, and in Firefox's case, that basically means "drop everything I was doing and just exit".

So, could it be that when you restart the computer, you proceed with a forced reboot? In normal computer restart circumstances, Firefox does save its state properly.

See also this extension:

• App Tab Initializer: https://addons.mozilla.org/firefox/addon/app-tab-initializer/

App tabs work perfectly and as described on my Mac, without changing any settings. My PC doesn't hold them at all.

Same problem! Was well excited at the prospect of app tabs!

But what's the point in pinning them if they're not going to stay pinned? Really gutted when I turned my PC on this morning and they were gone!

Hopefully they can work on a fix soon. In the meantime, back to bookmarks!

Has anyone heard if the new FF 4.1 helps?

FF just released Beta 1 of FF 5! So soon after releasing FF 4, that's amazing. Maybe FF 5 will be what we're waiting for.

For MAC users on Snow Leopard there is a glitch on how you shut down Firefox.

See my reply which has been raised as a bug report.

https://support.mozilla.com/en-US/questions/825628#answer-202340