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

Installed Firefox on Mac (OS 10.5.8) Will not open a browser window even after rebooting. Also - Must "Force Quit" to exit Firefox

  • 2 replies
  • 243 have this problem
  • 1 view
  • Last reply by tineke

more options

I installed Firefox on my Mac today (Mac OS 10.5.8) However File>New does not open browser window. Nothing happens. I rebooted and launced Firefox again but this did not help. I had been using Safari. Firefox is clearly running and I must do a "Force Quit" to quit Firefox.

This happened

Every time Firefox opened

I installed Firefox on my Mac today.

User Agent

Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10_5_8; en-us) AppleWebKit/533.17.8 (KHTML, like Gecko) Version/5.0.1 Safari/533.17.8

I installed Firefox on my Mac today (Mac OS 10.5.8) However File>New does not open browser window. Nothing happens. I rebooted and launced Firefox again but this did not help. I had been using Safari. Firefox is clearly running and I must do a "Force Quit" to quit Firefox. == This happened == Every time Firefox opened == I installed Firefox on my Mac today. == == User Agent == Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10_5_8; en-us) AppleWebKit/533.17.8 (KHTML, like Gecko) Version/5.0.1 Safari/533.17.8

All Replies (2)

more options

Hello John.

Hopefully this support article is what you need:

https://support.mozilla.com/en-US/kb/Firefox+will+not+start

Also, you may be interested in this one:

http://support.mozilla.com/en-US/kb/Firefox+hangs

more options

Ok, I have the answer dear Mac friends.

Go to your finder window - then at the bottom - include system files.

Search for firefox - delete everything - reinstall. Problem solved.