I’m trying to perform an action (e.g., launch an app) when I attach a USB device to my Mac. The issue is I’m not sure what Keyboard Maestro is looking for as the USB device name. Specifically, I am trying to launch a scanning application when I attach my Brother scanner to the Mac via plugging in the USB.
I used “Composite Device” as that’s what is shown in System Information (USB Device Tree).
You should be fine using "Composite Device", or whatever is shown in System Information's USB Device Tree. In case you're not aware, you can also configure the USB Device trigger to look for devices that only contain certain words in their names; you don't have to use the default "with exact name" option if another one like "with name containing" works better for your needs.
The name of the device as shown anywhere is irrelevant.
Instead, create the USB trigger, put the text focus in the name field, and plug in the device. Keyboard Maestro will fill in the name it sees, which is what you want to use.
OMFG. Almost too easy. This seriously made my day (not that the thing I’m trying to script was so life changing, but the mere fact Keyboard Maestro does this).