This screenshot of firefox highly consume CPU

Start Firefox in Troubleshoot Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration or userChrome.css is causing the problem.

• switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Themes
• do NOT click the "Refresh Firefox" button on the Troubleshoot Mode start window

• https://support.mozilla.org/en-US/kb/diagnose-firefox-issues-using-troubleshoot-mode
• https://support.mozilla.org/en-US/kb/troubleshoot-extensions-themes-to-fix-problems

You can create a new profile as a quick test to see if your current profile is causing the problem.

See "Creating a profile":

• https://support.mozilla.org/en-US/kb/profile-manager-create-remove-switch-firefox-profiles

If the new profile works then you can transfer files from a previously used profile to the new profile, but be cautious not to copy corrupted files to avoid carrying over problems.

• https://support.mozilla.org/en-US/kb/recovering-important-data-from-an-old-profile

Those are two different issues. As to the first I have seen one report of that message after you view Help > About Firefox which evidently triggers an update.

A high CPU usage in my experience is only temporary. I have linked a relevant article.

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

Thank you for your reply. But that doesn't still solve this problem. @cor-el changing to the default theme and creating a new profile doesn't do anything, the problem still occur even after i reinstall the firefox.

I'm sorry but i think the best thing to do for now is to uninstall the firefox. I wonder what instance that updating my firefox

Great news! I have found the source of problem. So, there is a MINING SCRIPT embedded to my CPU that makes Mozilla Firefox to use all of my CPU resource to mine. I don't know how the script can be embedded, my guess is from the malicious website that i visited or.. downloaded crack games