Firefox uses 30 % or more of the CPU? How to avoid?

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Dirki
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Firefox uses 30 % or more of the CPU? How to avoid?

Post by Dirki »

When Firefox is just open (without using it) it often uses 30 % or more of the CPU? Why is that? How could one avoid it?

At the moment there are about 10, 15 tabs open.
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DanRaisch
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Re: Firefox uses 30 % or more of the CPU? How to avoid?

Post by DanRaisch »

Do you have the same problem if you create a new profile and test it with no extensions or non-default themes installed and load only one tab?
http://kb.mozillazine.org/Profile_Manager
and
http://kb.mozillazine.org/Creating_a_ne ... on_Windows
Dirki
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Re: Firefox uses 30 % or more of the CPU? How to avoid?

Post by Dirki »

Thank you for the links.

With a single tab (or even more, 3 at the moment) I do not have that CPU usage (now up to 5 %) with the same Firefox / old profile.
- Windows 11 Home, 22H2, 64bit
- newest stable portable Firefox (not beta)
- newest stable portable Thunderbird (not beta)
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DanRaisch
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Re: Firefox uses 30 % or more of the CPU? How to avoid?

Post by DanRaisch »

Then the possibility is that the problem is a matter of the content in one or more of the tabs not being opened during this trial.
Dirki
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Re: Firefox uses 30 % or more of the CPU? How to avoid?

Post by Dirki »

Yes, is there a way to find out which tab / content might cause that CPU usage?

And what content can cause such CPU usage at all?
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DanRaisch
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Re: Firefox uses 30 % or more of the CPU? How to avoid?

Post by DanRaisch »

Videos and animations are obvious candidates. You could add one new tab at a time (from the list you had in the original situation) and check CPU usage after opening each tab.
Dirki
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Re: Firefox uses 30 % or more of the CPU? How to avoid?

Post by Dirki »

OK, I will try it the next time. So this CPU usage definetely is caused by such a content / the website / may be bad programming (of the page / website) and there is not anything one could do against it (but to load less pages / content at the same time), I assume.
- Windows 11 Home, 22H2, 64bit
- newest stable portable Firefox (not beta)
- newest stable portable Thunderbird (not beta)
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DanRaisch
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Re: Firefox uses 30 % or more of the CPU? How to avoid?

Post by DanRaisch »

That's the likely scenario but without testing as I suggested above it's not confirmed.
Dirki
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Re: Firefox uses 30 % or more of the CPU? How to avoid?

Post by Dirki »

Yes, I understand, thank you
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therube
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Re: Firefox uses 30 % or more of the CPU? How to avoid?

Post by therube »

There is about:performance, but I don't know if you'll get anything meaningful out of it?
Fire 750, bring back 250.
Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.1.19) Gecko/20110420 SeaMonkey/2.0.14 Pinball CopyURL+ FetchTextURL FlashGot NoScript
Dirki
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Re: Firefox uses 30 % or more of the CPU? How to avoid?

Post by Dirki »

Yes, may be the CPU usage for single tabs, it is displayed, do not know if it is the usage for opening the tab or while it is opened, I will try it the next time. Thank you
- Windows 11 Home, 22H2, 64bit
- newest stable portable Firefox (not beta)
- newest stable portable Thunderbird (not beta)
cmos
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Re: Firefox uses 30 % or more of the CPU? How to avoid?

Post by cmos »

maybe one of the web pages has a coinhive miner.
Dirki
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Re: Firefox uses 30 % or more of the CPU? How to avoid?

Post by Dirki »

A miner? In the Underground? In a coal mining or so? Yes, yes, of course.
- Windows 11 Home, 22H2, 64bit
- newest stable portable Firefox (not beta)
- newest stable portable Thunderbird (not beta)
cmos
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Re: Firefox uses 30 % or more of the CPU? How to avoid?

Post by cmos »

Google coinhive. Uses your CPU to mine bitcoins. On a lot of websites now.
Dirki
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Re: Firefox uses 30 % or more of the CPU? How to avoid?

Post by Dirki »

Alright, thank you
- Windows 11 Home, 22H2, 64bit
- newest stable portable Firefox (not beta)
- newest stable portable Thunderbird (not beta)
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