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

If you installed Firefox install with maintenance update it will check and install update. So when you install do "Custom" and you will see that the Maintenance update will be check to install and you can uncheck it.

What is the Mozilla Maintenance Service? https://support.mozilla.org/en-US/kb/what-mozilla-maintenance-service

You can also prevent this by creating password protected Admin/Owner account in the Windows admin/owner Account so even if it tries to update it will require the password and you can stop it as well.

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