Sometimes, when I have numerous tabs open in Firefox, one of those tabs will start consuming a lot of CPU%, and I want to know which tab is the culprit. Doing this is a very manual process for which I'd like to find automation.

I wish I had an application that could monitor firefox exclusively in a manner that produces concise output of only the firefox-facts I want to know.

I'm looking for a command/application that will list the processes of each tab running in firefox filtered to only include the following info for each tab-process:

  1. Process ID
  2. Webpage Address of Tab
  3. CPU % usage
  4. Memory used

Additionally, I'd like the info sorted by CPU % descending.

Basically, I hoping there exists a program like htop, but that's exclusively dedicated to just the pertinent stuff I want to monitor in Firefox (while leaving out all the details I don't care about).


You can type about:performance in the address bar of firefox. Then you will get a table where there will be pid of each tab of firefox with Resident Set size and Unique Set Size. And below this there will be some lines explaining the performance of each tab (like performing well) and if a tab is not performing well then it will show there and you can close that tab from there using the Close Tab option.

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  • 3
    about:performance gets a total redesign with more and better information from FF65. – pLumo Nov 27 '18 at 10:07
  • Suggestion: This answer might want to explain the recent changes made to about:performance before and after Firefox 65. There is no more table with "pid" or "set size". – clearkimura Feb 4 '19 at 7:50

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