We're calling on all EU-based Mozillians with iOS or iPadOS devices to help us monitor Apple’s new browser choice screens. Join the effort to hold Big Tech to account!

This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

when i open a new window i get this message: TypeError: Components.classes[cid] is undefined . Notice that i upgraded java and still get theese messages.

  • 1 cavab
  • 9 have this problem
  • 1 view
  • Last reply by TonyE

more options

In the first sessions of ff4 i had a message that was reffered to java. if i dont push ok button i cant work. Its really irritating

In the first sessions of ff4 i had a message that was reffered to java. if i dont push ok button i cant work. Its really irritating

All Replies (1)

more options

That indicates that you are using an add-on that is not compatible with Firefox 4. For details of how to troubleshoot this to find out what one is causing the problem see https://support.mozilla.com/kb/Troubleshooting+extensions+and+themes