Forward note: I am running Pop!_OS Linux (an Ubuntu derivative)
I set up one of the newer versions of LaserGRBL on my Linux laptop via PlayOnLinux (which provides a CMDL interface to Wine containers, amongst other things). LaserGRBL starts up with the default port set to “com10”, and apparently that is hard baked into the code or during installation. I was, however, able to find a workaround that now lets LaserGRBL work as expected.
As noted in my LightBurn post on the same subject (see: Cleaning up the device port names on startup), my OS creates the hot-plugged devices with the name ttyACM*. With that information I was able to use “wine regedit” to create a new port registry in " HKEY_LOCAL_MACHINE\\Software\\Wine\\Ports" that maps “com10” to /dev/ttyACM0. Now LaserGRBL starts up with with a reasonable working default.
Hope this helps.