When I open Firefox, suddenly I cannot change some of the settings (such as site notifications or default browser) and I get a message "Your browser is being managed by your organization". Then when I press it, I get a list: Policy Name Policy Value DisableAppUpdate true, DontCheckDefaultBrowser true
How can I regain the control and functionality of Firefox?
Note: I don't use Avast, nor AVG. Ubuntu version, 20.04. It's a personal computer.