The Mozilla Firefox browser is installed with several default features. One such feature is the JaveScript Debugger. The Debugger may launch when script errors are detected on a web page. Also, the script debugger may interfere with anti-malware installations, such as McAfee. Users often seek to disable the script debugger in Firefox, even if only temporarily. In addition, if websites are causing errors, check the Error Console from the Tools menu in Firefox to see the URLs that are causing the script errors.
Open the Firefox browser.
Click "Tools" on the top navigation bar, then click "Disable Script Debugger."
Click "Yes," then click "OK." The script debugger is disabled in Firefox.