X Virtual Framebuffer (Xvfb) is a great quick application to run applications that expect a
X11 server, but you don’t care to see the visual output.
sudo apt install xvfb
For more customization, I hear that it’s better to use xpra with Xdummy. I haven’t tried this myself yet, but if you experience issues with the application expecting
glx extensions, give it a shot.