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I am getting this error message when i try to open FF "ug-in object: TypeError: Components.classes[cid] is undefined"

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  • Last reply by cor-el

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This is the error message I get when i click to open FF after i downloaded the newest version: "ug-in object: TypeError: Components.classes[cid] is undefined" . The message is in the top left corner and not fully visible. i sent a message a few min ago so i am sending this b/c i copied the error message to help diagnose the problem.

This is the error message I get when i click to open FF after i downloaded the newest version: "ug-in object: TypeError: Components.classes[cid] is undefined" . The message is in the top left corner and not fully visible. i sent a message a few min ago so i am sending this b/c i copied the error message to help diagnose the problem.

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This issue can be caused by an extension that isn't working properly.

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

  • Don't make any changes on the Safe mode start window.

See: