As of EFL commit 4478654be185718ade7482df55c8643d3224fb37 GL compositing in E on X11 is broken. I get an error on startup:
Your display driver does not support OpenGL, GLSL, sharers or no OpenGL engines were compiled or installed for Evas or Ecore-Evas. Falling back to software engine.
You will need an OpenGL 2.0 (or OpenGL ES 2.0) capable GPU to use OpenGL with compositing.
Reverting to EFL commit 09f19c3c73b73eeee4201bb462bad9f2b5276409 re-enables GL compositing in E. E on Wayland doesn't appear to be affected.