1 - find a way to tell udev to not cancel firmware
4 - move /lib/udev/devices/ to tmpfiles
6 - trigger --subsystem-match=usb/usb_device
12 - remove RUN+="socket:"
16 - return object with *_unref()
17 - udev_monitor_from_socket()
18 - udev_queue_get_failed_list_entry()