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I am getting a javascript error on startup "Exc in ev handl: TypeError:this.oRoot.enable is not a function"

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When I start Firefox, I get an error box labeled [JavaScript Application] with the message "Exc in ev handl: TypeError: this.oRoot.enable is not a function" I then need to click the OK button before Firefox will start.

When I start Firefox, I get an error box labeled [JavaScript Application] with the message "Exc in ev handl: TypeError: this.oRoot.enable is not a function" I then need to click the OK button before Firefox will start.

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This issue can be caused by the McAfee Site Advisor extension


Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of the extensions or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox (Tools) > Add-ons > Appearance/Themes).