One Mac sees my Arduinos, the other doesn't

[J-M-L]

@ptillisch

turns out to be very difficult to uninstall it so I haven't been able to reproduce the problem yet in order to effectively research the full scope of the problem

Yes it’s hard - The SIP protection makes all this difficult

There is a process at the end of this discussion which is quite manual but basically ends up in removing all the files that were installed by the package.