If a HID-compatible braille display is connected over USB and has had custom commands added through Bluetooth, the custom commands do not work with USB.
Though there are many customizable commands with a braille display, they will not be retained once you connect to USB.
Note: the USB HID industry standard was announced in May 2018 with Apple being involved in its drafting, but Apple platforms may not yet officially support the standard.
Steps to reproduce
Bug First Encountered
Device(s) bug has been encountered on
How often the bug occurs
Re-add all customized commands to the display when connected over USB.