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Firefox uses all of my cpu

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  • Last reply by Geert1964

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Hello, I'm using Windows 7 and the latest version of Firefox. Since a cople of days, Firefox use 100 % of my CPU. It becoms very, very slow, even doesn't work anymore. I have tried every solution on mozilla support to this problem, but without succes. I even tried other things I found on the internet. It is a problem more people are confronted with. Greetings, Geert Tilmans

Hello, I'm using Windows 7 and the latest version of Firefox. Since a cople of days, Firefox use 100 % of my CPU. It becoms very, very slow, even doesn't work anymore. I have tried every solution on mozilla support to this problem, but without succes. I even tried other things I found on the internet. It is a problem more people are confronted with. Greetings, Geert Tilmans

Chosen solution

Please see if you have reports to send as per instructions in this URL that match your dates. https://support.mozilla.org/en-US/kb/firefox-crashes-asking-support

Please do this as I see you have a couple : Mozilla experiment, called 'Shield Studies'. Without even knowing it, you may have volunteered for this Mozilla experiment. Would you go to : Options => Privacy & Security => under 'Data Collection and Use' : Did you uncheck : 'Allow Firefox to install and run studies ' or is it checked  ?

To check if you are enrolled in these studies :

Type in the address bar about:studies

Any extensions that you see listed there, you can either disable or remove, just like this Safe Browsing version 4 (at the end of the experiment they will be disabled anyway). See for further information : https://support.mozilla.org/en-US/kb/shield

Please leave send info to Mozilla ticked or I would not have know this.

You can try to modify multi-process settings to see if this has effect. You can open the about:config page via the location/address bar. You can accept the warning and click "I accept the risk!" to continue.


set dom.ipc.processCount to 1 if it is currently set to a higher value (4) disable multi-process windows in Firefox

You can disable multi-process windows in Firefox by setting these prefs to false on the about:config page.

browser.tabs.remote.autostart = false browser.tabs.remote.autostart.2 = false

http://kb.mozillazine.org/about:config Also can reverse everything this tells you to enable it. http://www.ghacks.net/2016/07/22/multi-process-firefox/ Restart Firefox

Your Video Card Drivers are from 1-30-2015 Beschrijving: NVIDIA GeForce 7100 / NVIDIA nForce 630i

Please let us know if this solved your issue or if need further assistance.

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Chosen Solution

Please see if you have reports to send as per instructions in this URL that match your dates. https://support.mozilla.org/en-US/kb/firefox-crashes-asking-support

Please do this as I see you have a couple : Mozilla experiment, called 'Shield Studies'. Without even knowing it, you may have volunteered for this Mozilla experiment. Would you go to : Options => Privacy & Security => under 'Data Collection and Use' : Did you uncheck : 'Allow Firefox to install and run studies ' or is it checked  ?

To check if you are enrolled in these studies :

Type in the address bar about:studies

Any extensions that you see listed there, you can either disable or remove, just like this Safe Browsing version 4 (at the end of the experiment they will be disabled anyway). See for further information : https://support.mozilla.org/en-US/kb/shield

Please leave send info to Mozilla ticked or I would not have know this.

You can try to modify multi-process settings to see if this has effect. You can open the about:config page via the location/address bar. You can accept the warning and click "I accept the risk!" to continue.


set dom.ipc.processCount to 1 if it is currently set to a higher value (4) disable multi-process windows in Firefox

You can disable multi-process windows in Firefox by setting these prefs to false on the about:config page.

browser.tabs.remote.autostart = false browser.tabs.remote.autostart.2 = false

http://kb.mozillazine.org/about:config Also can reverse everything this tells you to enable it. http://www.ghacks.net/2016/07/22/multi-process-firefox/ Restart Firefox

Your Video Card Drivers are from 1-30-2015 Beschrijving: NVIDIA GeForce 7100 / NVIDIA nForce 630i

Please let us know if this solved your issue or if need further assistance.

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Hello, The problem is solved. Thanx. I think this: browser.tabs.remote.autostart = false browser.tabs.remote.autostart.2 = false did it! Regards, Geert1964