Hello,
In the following tutorial: https://docs.modalai.com/setup-adb/#host-computer-setup you give a tooltip on setting up a udev rule for the adb device, but once the VOXL is rebooted into bootloader mode, it appears as a different device (Bus 001 Device 010: ID 18d1:d00d Google Inc.) and fastboot is unable to discover it without root privileges.
I suggest you add the following to the tooltip:
SUBSYSTEM=="usb", ATTRS{idVendor}=="18d1", ATTRS{idProduct}=="d00d", MODE="0660", GROUP="plugdev", SYMLINK+="voxl-fastboot%n"
Thank you.