g2 command stalls indefinitely

[kylemcdonald]

On a Raspberry Pi running Ubuntu 20.04:

$ curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.38.0/install.sh | bash
$ source ~/.bashrc
$ nvm install lts/boron
$ node --version
v6.17.1
$ npm install -g g2core-api
$ ls /dev/ttyUSB*
/dev/ttyUSB1
$ g2 -p /dev/ttyUSB1 10mm.gcode

10mm.gcode:

G0 X0 Y0
G0 X10 Y10
G0 X0 Y0

I also tried without the -p argument but there seems to be an auto-detection issue right now.