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why is firefox running 4 instances in my task manager when i only have one window and tab open?

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  • 32 have this problem
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  • Last reply by Daddyo37

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restarted computer and its still doing this its hogging more resources than ever before now. fresh restart clicked on icon opened up firefox then task manager which reads 4 instances with varying sizes and i only have one window and one tab open, as you can see in attached screenshot; what is going on here? and why the resource hog this is insane?

restarted computer and its still doing this its hogging more resources than ever before now. fresh restart clicked on icon opened up firefox then task manager which reads 4 instances with varying sizes and i only have one window and one tab open, as you can see in attached screenshot; what is going on here? and why the resource hog this is insane?
Attached screenshots

Modified by N0FaC3

Chosen solution

Hello, this is because of e10s also known as multiproccess

To disable e10s/multiprocess go to about:config by typing it in your URL bar. Search for browser.tabs.remote.autostart using the search box on about:config. There may be multiple results. Set them all to false and restart the browser.

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All Replies (7)

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Chosen Solution

Hello, this is because of e10s also known as multiproccess

To disable e10s/multiprocess go to about:config by typing it in your URL bar. Search for browser.tabs.remote.autostart using the search box on about:config. There may be multiple results. Set them all to false and restart the browser.

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Hello, this is because of e10s also known as multiproccess

To disable e10s/multiprocess go to about:config by typing it in your URL bar. Search for browser.tabs.remote.autostart using the search box on about:config. There may be multiple results. Set them all to false and restart the browser.

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There option to limit one process does not work with the new Firefox Quantum so you will have to use and older version of Firefox and then it may actually work.

This does not work in the newest version of Firefox and will NOT run only one process. I am a 35 year computer tech with a LOT of experience. Firefox will need to patch the new Firefox Quantum to allow this option to work.

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ARREB said

There option to limit one process does not work with the new Firefox Quantum so you will have to use and older version of Firefox and then it may actually work. This does not work in the newest version of Firefox and will NOT run only one process. I am a 35 year computer tech with a LOT of experience. Firefox will need to patch the new Firefox Quantum to allow this option to work.

Actually it did work for me with Firefox 58.0 Quantum

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If it did you will be the first person I have ever heard of where it worked. I have tried it on multiple computers and op systems and have not seen it work on anything.

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After trying every fix out there I have given up on Firefox (Quantum 58.0.2). I see 6 processes running consuming way too much resources. When I set " browser.tabs.remote.autostart" it just slows down my browsing. Eventually I still see Memory usage climbing too high. The overall experience is horrible. My computer gets very slow. I have 6 gigs of Ram. I am not a Microsoft fan by any means. I avoid them like the plague. But Microsoft Edge runs rings around Firefox. I see 11 processes running in Edge yet the amount of memory usage is half what Firefox is. The response in Edge is quick and crisp. I think Firefox should remember the KISS principle. You seriously need to go back to a less complicated browser. I've used Firefox since it came out. I will no longer use it until urgently needed changes are made.

Totally Dissatisfied

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R3drang3r said

I think Firefox should remember the KISS principle. You seriously need to go back to a less complicated browser. I've used Firefox since it came out. I will no longer use it until urgently needed changes are made. Totally Dissatisfied

Amen, Brother! Same here.