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Firefox Version 54 is still running after closing the browser in windows 10

  • 10 replies
  • 6 have this problem
  • 2 views
  • Last reply by snydley

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I'm on a Windows 10 pc and just installed Firefox Version 54.0. After closing the browser, I run CCleaner Version ccleaner v5.31.6105 64-bit to clear cache but I get a message that Firefox is still open and asks me to let CCLeaner close it. I click 'Yes' but it does not close Firefox.

The same thing happens when I try to run Immunization on Spybot Search and Destroy - it says Firefox is still running and needs to be closed.

Even shutting down my pc and rebooting doesn't close Firefox. What's really strange is that I don't see Firefox even running in Task manager, so there's no process to click on to 'End Task'.

I've never had this problem before with any version of Firefox. I've used CCLeaner and Spybot and Firefox for years on many different versions of Windows.

I should note that CCleaner v5.31.6105 is the latest version. Since Spybot sees Firefox is still running like CCLeaner does, it makes me think the problem is with Firefox, but I can't be certain since I don't see it running in Task Manager.

Any help will be appreciated.

And, oh by the way, my brother says he has the same problem. Searching google did not find anything and I didn't see anything in mozilla support.

Please help! Thanks

I'm on a Windows 10 pc and just installed Firefox Version 54.0. After closing the browser, I run CCleaner Version ccleaner v5.31.6105 64-bit to clear cache but I get a message that Firefox is still open and asks me to let CCLeaner close it. I click 'Yes' but it does not close Firefox. The same thing happens when I try to run Immunization on Spybot Search and Destroy - it says Firefox is still running and needs to be closed. Even shutting down my pc and rebooting doesn't close Firefox. What's really strange is that I don't see Firefox even running in Task manager, so there's no process to click on to 'End Task'. I've never had this problem before with any version of Firefox. I've used CCLeaner and Spybot and Firefox for years on many different versions of Windows. I should note that CCleaner v5.31.6105 is the latest version. Since Spybot sees Firefox is still running like CCLeaner does, it makes me think the problem is with Firefox, but I can't be certain since I don't see it running in Task Manager. Any help will be appreciated. And, oh by the way, my brother says he has the same problem. Searching google did not find anything and I didn't see anything in mozilla support. Please help! Thanks

All Replies (10)

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You should be using firefox itself to clear it's cache. Clear history when Firefox closes

Many site issues can be caused by corrupt cookies or cache. In order to try to fix these problems, the first step is to clear both cookies and the cache. Note: This will temporarily log you out of all sites you're logged in to. To clear cache and cookies do the following:

  1. Click the menu button New Fx Menu, choose History, and then "Clear Recent History...".
  2. Under "Time range to clear", select "Everything".
  3. Now, click the arrow next to Details to toggle the Details list active.
  4. From the details list, check Cache and Cookies and uncheck everything else.
  5. Now click the "Clear Now" button.

Further information can be found in the Delete browsing, search and download history on Firefox article.

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bygabyga, Thanks, but it didn't log me out of anything, and besides, it doesn't answer my question nor resolve my problem.

Spybot can't run Immunization on Firefox since it's still open, even though I've closed the browser. And CCLeaner still complains about it too, so I'm not sure your suggestion really cleared anything.

For now, I'll give you the benefit of the doubt, but I really want Firefox to close when I log out from websites. If it's open, then I'm concerned about security.

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snydley said

I really want Firefox to close when I log out from websites. If it's open, then I'm concerned about security.

you use windows 10

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or you could just use (or force) private browsing

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Private Browsing may work going forward, but prior FireFox sessions are still active because they haven't closed.

I don't have this problem using Windows 7 and I am using the same version of CCLeaner on Win7 as I do on Win10.

Why does Win10 not close out Firefox version 54 and why can't I see the process in Task Mgr? Very confusing

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snydley said

Even shutting down my pc and rebooting doesn't close Firefox. What's really strange is that I don't see Firefox even running in Task manager, so there's no process to click on to 'End Task'.

I agree that makes no sense. Firefox certainly shouldn't be running hidden at startup. How are those programs finding firefox.exe running if the Task Manager -- on Windows 10, check the Details tab -- doesn't show firefox.exe running?

Some malware may start Firefox as a child process in the background, so if you haven't scanned recently, perhaps it would be a good time. You can supplement your regular security software with the on-demand scanners listed in our support article: Troubleshoot Firefox issues caused by malware.

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I don't know if Firefox is running hidden at startup, I never considered that. It's not in my Startup list.

I don't see firefox.exe on the Details tab, nor is it in the Processes tab.

I ran a scan and have no malware or anything virus-related found.

I reviewed the article Troubleshoot Firefox issues caused by malware, and nothing in there pertained to this issue.

I don't know if it Firefox 54, CCLeaner 5.31.6105 or Spybot Search and Destroy or Windows 10 that is causing the issue.

The notes in the release for Firefox 54 says: Chrome and Firefox now both support multithreading, but they do it in different ways. In Chrome, each and every tab you open gets its own content process. Ten tabs, 10 processes. One hundred tabs, 100 processes. This approach maximizes performance, but you pay a hefty penalty in memory consumption and (when applicable) battery life. Firefox doesn’t take this approach to the problem, but instead spins up to four content process threads by default.

I wonder if it's these 4 content process threads that get spun by default that is causing the issue.

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Not sure this has been stated or not r if you are doing so but after installing FF you should reboot before running CC. As well use MS Disk Cleanup before using CC as a after thought. Also what about running CC and telling it to ignore any FF issues it finds. Been a long time since used that so not sure if that is a option or not.

Modified by Shadow110

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snydley said

I wonder if it's these 4 content process threads that get spun by default that is causing the issue.

My understanding is that new firefox.exe processes are started as you open more pages, but none would be running until you start Firefox, and all should shut down when you exit Firefox (this often takes several seconds).

You could roll back the number of firefox.exe content processes from 4 to 1 to see whether that restores compatibility for the third party programs. I haven't tried this myself:

(1) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button promising to be careful.

(2) In the search box above the list, type or paste proc and pause while the list is filtered

(3) Double-click the dom.ipc.processCount preference and edit the value to 1, then click OK.

That should take effect on the next Firefox startup.

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jscher2000,

I liked your idea of rolling back the number of processes from 4 to 1 and was going to try it, but the issue has been mysteriously cleared up. CCLeaner and Spybot both have no problems with FF 54 anymore.

the odd thing about this resolution is, nothing changed. CCleaner is still the same version. Spybot is too. Same with FF. No updates.

So how does this problem cease to exist? No updates to my Win10 pc either, last one was 6-14.

Maybe something was wrong with my pc, unbeknownst to me, and that problem got fixed during all subsequent shutdowns and reboots.