Ok, thanks.
Hmm. That seems odd. Here on Linux desktop with an old GeForce 1xxx GPU and old 430.14 drivers, I show both as supported. I guess I don’t know without more details why what you’re trying isn’t working. However…
Why don’t you want to use a PBuffer for the surface?
What it sounds like you really want is surfaceless offscreen rendering support via EGL+GLES on an NVIDIA GPU+drivers. So use this:
For tips on how to make use of it, see:
With this, you don’t need a connection to the X server. But you can still render to an offscreen PBuffer if you want. Or just ignore it and use your FBO.
Anyway, this EGL context init method may get you want you want by taking a different route. You can then diff the two EGL context init methods and see what the crucial difference is that “breaks” your EGL_NO_SURFACE approach.