Comment 5 for bug 1473246

Oh nice thanks for the workaround, just tried a similar udev rule and it seems to work great. Re-enabled modem manager service, applied the MM ignore value with a rule, and can see the /dev/ttyACM* port stays the same between resets of the device. We'll add it to udev rules we tell folks to use when using the hardware (rule is here if you're curious: https://github.com/adafruit/Trinket_Arduino_Linux/blob/master/99-adafruit-boards.rules). Thanks!