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"Firefox is already running, but not responding" error

  • 12 svar
  • 3 har dette problem
  • 40 visninger
  • Seneste svar af rdenney

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Hello. I have been using Firefox off-and-on since the version 2.0, and there has been one bug that is plaguing me since 10+ years, and that is this error message that occurs when I close down Firefox and try to immediately reopen it (sometimes I wait 2-3 seconds just to avoid this error to no avail).

I am using version 65.0.2 (x64) now on latest Windows 10 version (on an MSI laptop with a spec of Intel i7 8750H cpu, Kingston SSD, 16 gb dual channel RAM and Nvidia RTX 2070 graphics card) and have been encountering this bug daily, and it really became so annoying that I'm considering reverting back to Chrome (which NEVER had this bug). This problem usually occurs when my previous Firefox session had more than 4 or so tabs, etc. but it also occurs when I just try to close and reopen the Firefox to test if the bug persists and 1 out of 5 times I get this bug and have to wait around 10 seconds for Firefox to realize there is a leftover session and offer me to close it before being able to open a new tab/window.

I have tried removing the .lock file from the profile folder (which DOES NOT remove itself when I end my session and gets recreated each time I restart a session), checking off the read-only mark from the profile folder, creating another profile and disabling hardware accelerating; but none of these made the slightest impact on the frequency I experience this problem. This thread from official Mozilla support also didn't help (https://support.mozilla.org/en-US/kb/firefox-already-running-not-responding ).

Should I just accept that this is the way Firefox works and that I need to wait 5-6 sec or so before attempting to reopen Firefox (as suggested here https://www.howtogeek.com/131004/how-to-fix-the-firefox-is-already-running-error/ (which dates back to 2012 and saddens me deeply that 7 more years of development changed nothing on this front)), or shut the Firefox down each time by killing it from the Task Manager; or could there maybe a fix to this? I had recently ditched Chrome since it froze my computer (a very rare bug related to the newer Windows 10 versions which occured only once to me, but felt serious enough that I uninstalled it), but if I can't find a reliable fix to this problem, I will probably just go back to Chrome where the bugs won't affect my daily usage.

Thank you for your help.

Hello. I have been using Firefox off-and-on since the version 2.0, and there has been one bug that is plaguing me since 10+ years, and that is this error message that occurs when I close down Firefox and try to immediately reopen it (sometimes I wait 2-3 seconds just to avoid this error to no avail). I am using version 65.0.2 (x64) now on latest Windows 10 version (on an MSI laptop with a spec of Intel i7 8750H cpu, Kingston SSD, 16 gb dual channel RAM and Nvidia RTX 2070 graphics card) and have been encountering this bug daily, and it really became so annoying that I'm considering reverting back to Chrome (which NEVER had this bug). This problem usually occurs when my previous Firefox session had more than 4 or so tabs, etc. but it also occurs when I just try to close and reopen the Firefox to test if the bug persists and 1 out of 5 times I get this bug and have to wait around 10 seconds for Firefox to realize there is a leftover session and offer me to close it before being able to open a new tab/window. I have tried removing the .lock file from the profile folder (which DOES NOT remove itself when I end my session and gets recreated each time I restart a session), checking off the read-only mark from the profile folder, creating another profile and disabling hardware accelerating; but none of these made the slightest impact on the frequency I experience this problem. This thread from official Mozilla support also didn't help (https://support.mozilla.org/en-US/kb/firefox-already-running-not-responding ). Should I just accept that this is the way Firefox works and that I need to wait 5-6 sec or so before attempting to reopen Firefox (as suggested here https://www.howtogeek.com/131004/how-to-fix-the-firefox-is-already-running-error/ (which dates back to 2012 and saddens me deeply that 7 more years of development changed nothing on this front)), or shut the Firefox down each time by killing it from the Task Manager; or could there maybe a fix to this? I had recently ditched Chrome since it froze my computer (a very rare bug related to the newer Windows 10 versions which occured only once to me, but felt serious enough that I uninstalled it), but if I can't find a reliable fix to this problem, I will probably just go back to Chrome where the bugs won't affect my daily usage. Thank you for your help.

Ændret af Unbeknownst den

Alle svar (12)

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Unbeknownst said

when I close down Firefox and try to immediately reopen it

You should give the browser, in fact any program, time to finish closing. Wait about 10 seconds.

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FredMcD said

Unbeknownst said
when I close down Firefox and try to immediately reopen it

You should give the browser, in fact any program, time to finish closing. Wait about 10 seconds.

Well d'oh! I had mentioned I also tried waiting 2-3 seconds to allow it to close down to no avail. I wonder, why of all programs Firefox is the only one with this issue, and when we compare it to Chrome which not only loads blazingly fast, but you can also close and reopen it with miliseconds apart without having any halt, pause or issue whatsoever (and to think Chrome is much more of a RAM and CPU hog(!)).

Thank you for reading this and providing your insight, but it doesn't say anything new to me as I had already linked a link from 2012 to a website recommending to be patient.

Ændret af Unbeknownst den

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Unbeknownst said

Well d'oh! I had mentioned I also tried waiting 2-3 seconds to allow it to close

FredMcD said

10 seconds.
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FredMcD said

Unbeknownst said
Well d'oh! I had mentioned I also tried waiting 2-3 seconds to allow it to close

FredMcD said

10 seconds.

I don't appreciate you taking the parts you see fit from what I've written to "seemingly" answer my question. It would be much better if you just wouldn't reply so that I can move forward a constructive discussion.

And by the way, I already mentioned that this doesn't happen each time I relaunch Firefox, but only happens in 1 in 3 to 1 in 5 times, so how can this not be a bug when its occurance is completely random (not depending on the number of closed tabs, etc.)? And can you also elaborate on all programs needing 10 seconds of time to finish closing? I have never encountered one except Firefox, and Chrome seems to work perfectly fine even if you close 250 tabs and relaunch it within the same second.

I must say though, I am appalled to see how such a person who ranks amongst the top 10 contributors be so manipulative and have bossy manners that contribute to no fruitful discussion.

Then again, thanks for taking your time on my issues.

Ændret af Unbeknownst den

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I am not being manipulative. I am giving you facts. Many complicated programs run sub-programs. Those need to be shut down before the main can shut itself down. Thus, 10 seconds.

As you don't want my advice, goodbye.

Hailing Frequencies Closed.

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Unbeknownst said

... Should I just accept that this is the way Firefox works and that I need to wait 5-6 sec or so before attempting to reopen Firefox (as suggested here https://www.howtogeek.com/131004/how-to-fix-the-firefox-is-already-running-error/ (which dates back to 2012 and saddens me deeply that 7 more years of development changed nothing on this front)), or shut the Firefox down each time by killing it from the Task Manager; or could there maybe a fix to this? ...

Yes, accept that as the way Firefox works!

As far as that article from 2012 and 7 years more development goes, Firefox can take longer to completely close down than it did 7 years ago it some cases. There are many more files that are kept open while Firefox is running than there were years ago; files that do need time to be closed before Firefox is ready to be re-opened.

And its not like the Mozilla developers have done nothing to speed things up when Firefox is closed down. If you have spent anytime perusing the files in the Profile folder, you would have seen that Firefox has many more files in the Profile folder than were present years ago and with Quantum 57 there was fairly large increase in the number of files added. Most notably and related to this "Firefox is already running ..." topic, with Firefox running see the number of "temporary" *.sqlite-wal and *.sqlite-shm files that will disappear when Firefox is closed. There are 4 pairs of that type of file in use while Firefox is running for temporary storage of user data while Firefox is being used; when Firefox closes down, the data in those files gets written to the "master" .sqlite file during the shutdown process. The developers need to balance the speed of Firefox when it is being used vs. the shutdown time it takes to close those "in use" files.

Start installing extensions and the time for a full closure may increase due to how each extension was written. Many extensions have transitioned away from the Legacy .rdf, .txt, .dat & .xml format for storing their data and are using the modern .sqlite, .json, and .mozlz4 file formats for storing data; that too can lengthen the shutdown time.

Bottom line is that the shutdown time is far less of a concern for developers than the launch time and the speed of Firefox when it is being used.

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the-edmeister said

Unbeknownst said
... Should I just accept that this is the way Firefox works and that I need to wait 5-6 sec or so before attempting to reopen Firefox (as suggested here https://www.howtogeek.com/131004/how-to-fix-the-firefox-is-already-running-error/ (which dates back to 2012 and saddens me deeply that 7 more years of development changed nothing on this front)), or shut the Firefox down each time by killing it from the Task Manager; or could there maybe a fix to this? ...

Yes, accept that as the way Firefox works!

As far as that article from 2012 and 7 years more development goes, Firefox can take longer to completely close down than it did 7 years ago it some cases. There are many more files that are kept open while Firefox is running than there were years ago; files that do need time to be closed before Firefox is ready to be re-opened.

And its not like the Mozilla developers have done nothing to speed things up when Firefox is closed down. If you have spent anytime perusing the files in the Profile folder, you would have seen that Firefox has many more files in the Profile folder than were present years ago and with Quantum 57 there was fairly large increase in the number of files added. Most notably and related to this "Firefox is already running ..." topic, with Firefox running see the number of "temporary" *.sqlite-wal and *.sqlite-shm files that will disappear when Firefox is closed. There are 4 pairs of that type of file in use while Firefox is running for temporary storage of user data while Firefox is being used; when Firefox closes down, the data in those files gets written to the "master" .sqlite file during the shutdown process. The developers need to balance the speed of Firefox when it is being used vs. the shutdown time it takes to close those "in use" files.

Start installing extensions and the time for a full closure may increase due to how each extension was written. Many extensions have transitioned away from the Legacy .rdf, .txt, .dat & .xml format for storing their data and are using the modern .sqlite, .json, and .mozlz4 file formats for storing data; that too can lengthen the shutdown time.

Bottom line is that the shutdown time is far less of a concern for developers than the launch time and the speed of Firefox when it is being used.

Thank you for this detailed and explanatory answer to my question.

You mentioned some changes that have been implemented with Firefox Quantum, and I can say that while Quantum to me was Firefox learning its lesson on launch speed from Chrome and other Chromium-based browsers, those browsers always shut themselves down almost instantly when the user presses shutdown button and then the user can immediately relaunch the browser. My gripe here is that while Firefox now loads really fast and also performs even better than the Chromium browsers while also occupying less CPU and RAM, it still shuts itself down very slowly that the end user encounters this dreaded "Firefox is already running..." error message unacceptably often.

Also, the 2012 article I linked on How-To Geek literally starts with the following sentence: "The “Firefox is already running, but is not responding” error has haunted Firefox users for years." As I mentioned in my original post, I remember encountering this issue Firefox 2 or 3 onwards and as a person who takes Mozilla over Google any day, it just saddens me to see that in 10+ years so little has been done on this front of Firefox, and it also was the reason I switched to Chrome for many years until Chrome started to freeze Windows 10 computers.

I had even started to think maybe I'm one of those very few people that encounters this message because I often close and relaunch Firefox within a short time window; but seeing the threads on support forums, tech blog articles, etc. I realized that this problem is not that rare and lots of users encounter it, so I wanted to post here to maybe get some insight on it. And your post actually gave me insight and suggested me reasons why this is still happening even after the drastic jump to the Quantum and what could be done in future to alleviate this issue; so thank you once again for taking your time to provide your insight on this.

Ændret af Unbeknownst den

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the-edmeister said

Start installing extensions and the time for a full closure may increase due to how each extension was written. Many extensions have transitioned away from the Legacy .rdf, .txt, .dat & .xml format for storing their data and are using the modern .sqlite, .json, and .mozlz4 file formats for storing data; that too can lengthen the shutdown time.

Today I installed the new version 66 and I have to say, the problem doesn't feel near as bad as before. It isn't completely eradicated, but it became much rarer now and it takes a lot less time for Firefox to be responsive after getting the error message.

I'm contemplating that this has got to do with "Extensions now store their settings in a Firefox database, rather than individual JSON files, making every site you visit faster" (especially considering what you suggested as a probable cause for this delay in shutdown) and "Improved performance and reduced crash rates by doubling web content loading processes from 4 to 8" entries from the changelog.

EDIT: It became less frequent with the update but it definitely is there so that I was still noticing it daily so I switched to Opera.

Ændret af Unbeknownst den

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This problem has been going on for YEARS...in all sorts of hardware / software configuration end user environments.

The common denominator is Mozilla Firefox. It is very disappointing that Mozilla won't step up and fix this nagging error condition once and for all.

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original roundball said

This problem has been going on for YEARS...in all sorts of hardware / software configuration end user environments. The common denominator is Mozilla Firefox. It is very disappointing that Mozilla won't step up and fix this nagging error condition once and for all.

This is my BIGGEST gripe with Firefox. The help file fixes don't seem to fix the problem, or apply. I've even had this error occur when I shut down the browser with CTRL+SHIFT+Q (although not as often)

When the problem occurs, and I close the pop-up, Firefox is always able to restart. So rather than giving me a pop-up, then doing whatever to get started, why not just do the fix w/o the pop-up?

Also, why not make clicking X to close a window do whatever CTRL+SHIFT+Q does?

Ændret af rdenney den

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rdenney said

original roundball said
This problem has been going on for YEARS...in all sorts of hardware / software configuration end user environments. The common denominator is Mozilla Firefox. It is very disappointing that Mozilla won't step up and fix this nagging error condition once and for all.

This is my BIGGEST gripe with Firefox. The help file fixes don't seem to fix the problem, or apply. I've even had this error occur when I shut down the browser with CTRL+SHIFT+Q (although not as often)

When the problem occurs, and I close the pop-up, Firefox is always able to restart. So rather than giving me a pop-up, then doing whatever to get started, why not just do the fix w/o the pop-up?

Also, why not make clicking X to close a window do whatever CTRL+SHIFT+Q does?

I share exactly the same thoughts with you on how closing the pop-up fixes Firefox up and then why do we still need this damned pop-up after all these years.

I was unaware that there was a second quit option with CTRL+SHIFT+Q, but hearing that even this does not eliminate the problem is saddening, to say the least.

Even though I fully wanted to support Firefox and use it as my only browser this freaking issue that persists since the stone age just bugged me too much that I switched to Opera. After hearing that Firefox will be bringing a paid option, I'm not sure what I should think of the Mozilla Foundation anymore.

Ændret af Unbeknownst den

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CTRL+Shift+Q is supposed to be a clean-shutdown of Firefox, and does lessen the chance of the error, but is not 100%, so there is something else going on.