What are you trying to get it to do - open with a home page or restore the previous session? Did you check the setting in Options > General > "When Firefox starts:"? Do you have the problem if you use File > Exit or right-click the icon shortcut and choose Quit?

Try the following:

1. Go to about:config
2. Locate browser.sessionstore.resume_from_crash
3. Change this string's value to false

Please report back soon.

I used to have this issue too, but I did the steps about and it fixed the issue.

Note that it is better to use "Firefox > Exit Firefox" to close Firefox, especially if you have problems like this when Firefox doesn't close properly.

See also:

• "Hang at exit": http://kb.mozillazine.org/Firefox_hangs
• "Firefox hangs when you quit it": https://support.mozilla.org/kb/Firefox+hangs

Thank you for your replies!

Yes I checked the setting. It is set to "Show my windows and tabs from last time".

I want Firefox to open all my tabs from the last session on restart. It works fine whenever I close Firefox with opened tabs. It reloads them on restart.

The problem occurs when I close Firefox with a single New Tab regardless of how I start it again: with the tray icon or by opening a URL.

Firefox works fine if I close it with the File > Exit or Firefox > Exit options.

I found the browser.sessionstore.resume_from_crash setting earlier. So it seems Firefox crashes on exit, or thinks it crashed last time. I can disable the resume_from_crash but then what if firefox crashes? I will loose all my work.

Is it a bug? If it is: is it already reported?

You will have to find what is causing Firefox to hang (i.e. not close properly) when you use the close X.

This can also be caused by a hanging plugin-container process, so check the Task Manager to see which Firefox processes are still present.

When I open a page that cointains flash items (like index.hu) there are: firefox.exe, plugin-container.exe and two FlashPlayerPlugin_11_8_800_168.exe processes visible in Windows Task Manager. If I close all tabs then close Firefox, all of these processes stops.

When a more simple page is opened (like support.mozilla.org) then there is only the firefox.exe. If all tabs then Firefox is closed, the process stops immediately.

In both of the cases Firefox starts with the Restore Session tab next time.

Does the sessionstore.js file end with: "state":"running" ?

If Firefox closes correctly then you should see "state":"stopped" at the end of the file.

• http://kb.mozillazine.org/sessionstore.js

The "stopped" string is not in the sessionstate.js file. This is how it ends:

"session":{"state":"running","lastUpdate":1380265525143,"startTime":1380203684582,"recentCrashes":0},"scratchpads":[]}

That means that Firefox wasn't able to close the file properly (i.e. something went wrong before reaching this stage in the closing process) and change "state":"running" to "state":"stopped".

Ok. This looks like a bug. I will double check again without extensions then I am going to check if there is already a reported bug for this issue.

Have you found any answers to this problem yet?

If not, I have had the same problem in the past and for a long time was continually aggravated by it until I read somewhere that Firefox should be closed by clicking on the Firefox icon at the top left and clicking EXIT.

I have not lost tabs once since closing that way. Yes, it takes an extra second, but it has been worth it in saved aggravation over the last year or two.

Yes. That is a workaround.

This issue seems to be a bug. I have checked about a 1000 bugreports on Firefox bugzilla but unfortunately I haven't found any regarding this problem. So it seems the developers don't know this problem.

As I am not a registered Firefox contributor I cannot file a bugreport. I have already filled a Firefox feedback describing this problem but I haven't received any aswer yet.