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I receive a message every time before starting Firefox which is " what happened:TypeError;Components.classes['@mozilla.org/extention/manager;1] is undefined " . please let me know a solution to fix the error message

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  • Last reply by cor-el

AsadZaman
AsadZaman
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I receive a message every time before starting Firefox which is " what happened:TypeError;Components.classes['@mozilla.org/extention/manager;1] is undefined " . please let me know a solution to fix the error message

I receive a message every time before starting Firefox which is " what happened:TypeError;Components.classes['@mozilla.org/extention/manager;1] is undefined " . please let me know a solution to fix the error message

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cor-el
cor-el
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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 extensions is causing the problem (switch to the DEFAULT theme: Firefox (Tools) > Add-ons > Appearance/Themes).

If it does work in Safe-mode then disable all extensions and then try to find which is causing it by enabling one at a time until the problem reappears.

  • Use "Disable all add-ons" on the Safe mode start window to disable all extensions.
  • Close and restart Firefox after each change via "File > Exit" (Mac: "Firefox > Quit"; Linux: "File > Quit")