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Firefox Quantum is the biggest memory hog ever

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I have already opened such topic before, but Firefox Quantum uses markedly more memory than the previous version.

I had one window with eleven tabs open (Firefox 57.0 64-bit). Killing the browser using taskkill command released 1.9 megabytes of memory, according to Task Manager (Windows 10 Professional 64-bit). Yes, there had been some tabs open previously, which I closed later. But if memory does not get freed after closing tabs, then what is the point of closing them? – Let them stay open.

In another case killing Firefox with 21 tabs in a single window released 2,7 megabytes of RAM.

Surfing now slows down the computer (a laptop) substantially.

I really felt how heavier this version of Firefox is after installing it.

I am thinking about using Chrome since it is much lighter while providing enough functionality. It is after 21 years of using Firefox line (since Netscape Navigator 3.0).

I have already opened such topic before, but Firefox Quantum uses markedly more memory than the previous version. I had one window with eleven tabs open (Firefox 57.0 64-bit). Killing the browser using taskkill command released 1.9 megabytes of memory, according to Task Manager (Windows 10 Professional 64-bit). Yes, there had been some tabs open previously, which I closed later. But if memory does not get freed after closing tabs, then what is the point of closing them? – Let them stay open. In another case killing Firefox with 21 tabs in a single window released 2,7 megabytes of RAM. Surfing now slows down the computer (a laptop) substantially. I really felt how heavier this version of Firefox is after installing it. I am thinking about using Chrome since it is much lighter while providing enough functionality. It is after 21 years of using Firefox line (since Netscape Navigator 3.0).

All Replies (5)

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Megabytes...by glad not gigabytes.

You could try this please : Go the Menu then Tools --> Options --> Performance and untick everything. change the recommended size lower then see how it runs. O= no use of CPU Cores.

Hardware Acceleration might have also been a issue so turn it off.

Run it later and see as you turn things back on and test it, and again. Restart Firefox after making these changes please.

There are other things to try if this does not work, just remember are taking the use of Multi-core processioning out if go to 0.

I would suggest updating anything you can, like go to the Motherboard Manufactures site so see if updates or if no longer support, all so update you video Card Drivers before it goes out of support.

Also : Could you go to the Firefox Menu Bar then--> Help --> Troubleshooting Information and copy the contents of that page and paste them here into a reply on the forum. Please take a look in the Accessibility Section if Accessibility is set to "True" there.

If yes, can you please Copy/Paste this whole section into a reply in the forum and see if the following fixes the performance problem: Go to the Firefox 3 Bar Menu --> Options --> Privacy & Security then under Permissions check the setting to prevent Accessibility Services from accessing your browser.

Can also do these things if feel the need : Start Firefox in Safe Mode {web link} by holding down the <Shift> (Mac=Options) key, and then starting Firefox.

A small dialog should appear. Click Start In Safe Mode (not Refresh). Is the problem still there?

https://support.mozilla.org/kb/Firefox+is+already+running+but+is+not+responding

https://support.mozilla.org/en-US/kb/firefox-slow-how-make-it-faster

https://support.mozilla.org/en-US/kb/firefox-uses-too-many-cpu-resources-how-fix

https://support.mozilla.org/en-US/kb/firefox-uses-too-much-memory-ram

https://support.mozilla.org/en-US/kb/firefox-hangs-or-not-responding

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

Modified by Shadow110

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Sorry, of course it was gigabytes.

Unfortunately, your solution did not change anything substantially, and I am a happy user of Google Chrome now, which is incomparably lighter.

Modified by DVS75

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I see mine is using 1.1 GB of 16.

This isn't an issue for me, it's fast, and works great, but what is taking up that much space?

I have 4 tabs open.

Task Manager shows 7 of something.

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You will be able to see the actual amount taken by Firefox only after killing it and comparing with the total amount used after that.

The difference is usually quite big with what is shown per process,

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I did "End Task" and re-opened the browser.

I didn't go to any web page, and it starts with 4 of something, and 376 MB