Enable GLX extension in Xvfb in Xquartz

Question

The version of Xvfb included in Xquartz on MacOS doesn't support GLX:

$ Xvfb +extension GLX
[mi] Extension "GLX" is not recognized
[mi] Only the following extensions can be run-time enabled:
[mi]    Generic Events
[mi]    Composite
 ...

Is it feasible to enable it? What is involved?

Edited to add: I tried running Xvfb with the GLX extension on a Linux VM. It runs fine, but it doesn't actually render the OpenGL graphics. Perhaps I used the wrong config for the display. I used

Xvfb :1 -screen 0 1024x768x24 +extension GLX +render -noreset -fbdir temp >xsession.log 2>&1 &

or perhaps Xvfb just doesn't render OpenGL.