Can't open other files, Cura doesn't close

[steven5655]

Cura Version

5.9.0

Operating System

Mac OS X Sequoia 15.1

Printer

Ender 3 V3 SE

Reproduction steps

Open a file then when I close cura doesn't close or open any other file I have to right click and quit few time to close it and open another file

Actual results

Cura doesn't close or open another file

Expected results

Cura close or open another file

Add your .zip and screenshots here ⬇️

No zip

[GregValiant]

Thanks for the report.
There have been a few instances where users had devices plugged in to a computer USB port (headphones and such) and internally those devices are configured as "Serial Devices". Cura's "USB Printing" plugin is enabled by default and so when Cura starts - it sees the serial device and assumes it's a printer. Cura keeps sending "M105" to a pair of headphones which keep going "What??" and the UI is unresponsive while that is going on.
Go to the MarketPlace in Cura and click on the "Gear" icon. Scroll down and disable "USB Printing". Restart Cura and see if that resolves the problem.