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

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

more options

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?

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)

more options

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

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

more options

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.

more options

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.