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Firefox won't open on Mac, get error The application “Firefox.app” can’t be opened.

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My OS is Catalina 10.15.4. Firefox worked fine until today. I have removed and reinstalled Firefox. I have setup a new profile. Firefox will not open in safe mode.

What else should I do?

Attached screenshots

Modified by Lamar

All Replies (3)

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This video goes over what you might be able to do to resolve it

https://www.youtube.com/watch?v=i9TtoOJjGpU

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I tried that but it didn't help. The video refers to an executable that has somehow corrupted to a txt file. I ran the terminal routine but it didn't help because I think the firefox file isn't corrupt. The firefox executable in my package contents is a Unix executable.

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Hi, hold down Shift (Option key on Mac) when you start Firefox to start in Safe Mode. ... You may need to restart Firefox after enabling some add-ons. Try starting from the Start Menu > Mozilla Firefox. If it works; in Win10 you can drag from the Start Menu to your Desktop or right click and pin the icon in the Task Bar.

Thank you.