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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

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.

All Replies (1)

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: