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Firefox hangs after unlocking the computer, and occasionally when opening a URL from another app

  • 2 replies
  • 1 has this problem
  • 16 views
  • Last reply by semicoleon

semicoleon
semicoleon
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I've had some extremely weird hangs in Firefox particularly around when I unlock my (Windows 10) PC. It happens extremely consistently even in troubleshoot mode and after several reinstalls of Firefox. Occasionally it also seems to happen when an external application asks the operating system to open a URL (Since Firefox is my default browser this of course causes Firefox to open a new tab... eventually).

The exact amount of time the hang lasts seems to vary quite a bit, but it's usually less than 30 seconds. Even when the hang lasts a long time I have never seen Windows indicate that the app is not responding which seems to imply it's not getting stuck so much as getting slowed down by something.

I can reproduce the unlocking version of this issue extremely reliably. In Task Manager I can see all of the Firefox processes sitting at 0% CPU, but when I lock and unlock the computer (with Windows Key + L to lock) exactly one of the Firefox processes (the ones grouped together in task manager) shoots up to ~8% CPU for the duration of the hang. The process that reliably spikes is using~500MB of memory while all of the other Firefox processes average about 40MB of memory so I assume the spike is happening in the main Firefox process. One of the two Firefox processes that ISN'T grouped together with any others in Task Manager also spikes to ~4% CPU when the hang starts fairly reliably, and some of the other grouped processes usually spike but to a much lesser degree and for a much shorter time.

I've had some extremely weird hangs in Firefox particularly around when I unlock my (Windows 10) PC. It happens extremely consistently even in troubleshoot mode and after several reinstalls of Firefox. Occasionally it also seems to happen when an external application asks the operating system to open a URL (Since Firefox is my default browser this of course causes Firefox to open a new tab... eventually). The exact amount of time the hang lasts seems to vary quite a bit, but it's usually less than 30 seconds. Even when the hang lasts a long time I have never seen Windows indicate that the app is not responding which seems to imply it's not getting stuck so much as getting slowed down by something. I can reproduce the unlocking version of this issue extremely reliably. In Task Manager I can see all of the Firefox processes sitting at 0% CPU, but when I lock and unlock the computer (with Windows Key + L to lock) exactly one of the Firefox processes (the ones grouped together in task manager) shoots up to ~8% CPU for the duration of the hang. The process that reliably spikes is using~500MB of memory while all of the other Firefox processes average about 40MB of memory so I assume the spike is happening in the main Firefox process. One of the two Firefox processes that ISN'T grouped together with any others in Task Manager also spikes to ~4% CPU when the hang starts fairly reliably, and some of the other grouped processes usually spike but to a much lesser degree and for a much shorter time.

All Replies (2)

mamoonrashidrazmal
mamoonrashidrazmal
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hello there, actually reasons for internet browser to hang is many, such as Firefox hangs can be caused by missing or corrupt software files, Plugin or Extension System Resources Conflicting Software System Registry mess-up etc

you have to check each one. especially plugin or extensions. It's possible that a third-party plugin or extension is causing Firefox to hang. Ensure you're running the latest versions of any plugins and extensions you have installed. These third-party tools can be temporarily disabled from the Add-ons Manager tab. One troubleshooting method is to disable each plugin or extension in turn and check if the problem is solved. If you're able to identify the cause of the persistent hanging, uninstall and reinstall the plugin or extension , if this does work please let me know

semicoleon
semicoleon Question owner
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mamoonrashidrazmal said
Plugin or Extension System Resources Conflicting Software System Registry mess-up etc


I've tried manually disabling the extensions I have installed before and the problem didn't stop. I'm also currently running Firefox in troubleshooting mode which disables extensions in addition to doing a bunch of other stuff and that doesn't seem to have solved the problem either.

I don't know enough about Windows internals to screw around with the registry but if there are things I should check I can do that.