Join the AMA (Ask Me Anything) with the Firefox leadership team to celebrate Firefox 20th anniversary and discuss Firefox’s future on Mozilla Connect. Mark your calendar on Thursday, November 14, 18:00 - 20:00 UTC!

This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Firefox on Mac (a lot of tabs) is constantly on top of CPU usage. How can I discover which tab(s) is/are resposnible for high CPU usage ?

  • 2 replies
  • 1 has this problem
  • 6 views
  • Last reply by P5555

more options

I have a lot of Firefox windows with multiple tabs in each (this is my way of working ...). I can see in the Activity Monitor that the Firefox is the most active application in terms of CPU and energy consumption on my Mac (it just drains battery ..). I used the Task Manager but it doesn't help much. Is there any better, more detailed way how to display which tab could be blamed for CPU usage ?

I have a lot of Firefox windows with multiple tabs in each (this is my way of working ...). I can see in the Activity Monitor that the Firefox is the most active application in terms of CPU and energy consumption on my Mac (it just drains battery ..). I used the Task Manager but it doesn't help much. Is there any better, more detailed way how to display which tab could be blamed for CPU usage ?

All Replies (2)

more options

Hello p5555,

As neither the Activity Monitor nor the Task Manager give you what
you're looking for; would you try this please :

Type in the address bar about:performance and press Enter.

You could also try about:memory.

Any good ?

more options

But Task Manager is the same as about:performance, isn't it ?