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When starting Firefox 4 I am presented with a JavaScript Application message "TypeError ksClass is undefined"

  • 1 reply
  • 17 have this problem
  • 2 views
  • Last reply by cor-el

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How do I get rid of this?

The Java Add ons only allow disable; how do I remove them?

How do I get rid of this? The Java Add ons only allow disable; how do I remove them?

All Replies (2)

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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 > Themes).

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

See:


See:


Your More system details list shows that you have an incompatible display driver for your ATI Radeon HD 4800 Series graphics display and that WebGL is disabled. You can try to update that driver as recommended on the Help > Troubleshooting Information page.

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Thanks muchly; problem solved.