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Can’t open Firefox in Mac OS 10.15. Error message saying it is not supported.

  • 5 replies
  • 3 have this problem
  • 95 views
  • Last reply by cor-el

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My computer auto-upgraded to Mac OS Catalina 10.15. When I try to run Firefox, I receive an error message that the application is not supported by OS 10.15. I’ve downloaded the latest version of Firefox. Any suggestions?

My computer auto-upgraded to Mac OS Catalina 10.15. When I try to run Firefox, I receive an error message that the application is not supported by OS 10.15. I’ve downloaded the latest version of Firefox. Any suggestions?

Chosen solution

Try to wait for Catalina beta 6

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All Replies (5)

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Hi,

I think we have to create a ticket on our bugzilla so that the teams can read it

https://bugzilla.mozilla.org

thank's

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See:

  • Bug 1563631 - [Mac 10.15] Firefox 68 and 67.0.2+ cannot be opened on macOS 10.15 Beta

(please do not comment in bug reports
https://bugzilla.mozilla.org/page.cgi?id=etiquette.html
)

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I too have similar problem when launching Firefox after Mac OS Catalina 10.15 beta upgrade. See attached screenshot.

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n0name I suspect you have the same problem as https://support.mozilla.org/en-US/questions/1265998

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Chosen Solution

Try to wait for Catalina beta 6