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how can I remove this "What happened.classes[@Mozilla.org/extensions/manager] is undefined"

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  • 6 have this problem
  • 3 views
  • Last reply by jackimms

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Heading - Java Script Application followed by "What happened,Type error Components,classes[@Mozilla.org/extentions/manager] is undefined" I do not understand the problem or how to get rid of it.

Heading - Java Script Application followed by "What happened,Type error Components,classes[@Mozilla.org/extentions/manager] is undefined" I do not understand the problem or how to get rid of it.

Chosen solution

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")

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Chosen Solution

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")

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I removed "Tracker Toolbar" from the Add-on list under Safe Mode. The problem does not occur now when I stat Firefox. Jack