There is not much. I used this as reference:

https://github.com/fendevel/Guide-to-Modern-OpenGL-Functions

buzzelliart said:
more advanced features/techniques like AZDO

AZDO is just a naming convention nVidia adopted years ago to tell that OpenGL can approach Vulkan under some conditions. Main principles are avoid to switch buffers, reduce number of draw calls and use DSA (‘named’ prefixed functions). You can add vertex attrib binding to this list depending on things.

Except for tessellation and compute shaders, GL 3.3 already gives you most of what GL is capable. GL 4.x are mainly adding conveniency / speed stuffs: DSA, SSBOs, and the ‘ugly’ non-mandatory bindless textures or SPIRV for example.

You can also try to OpenGL wiki, it's quite well-formed if you already know OpenGL enough.

Learn OpenGL

https://learnopengl.com/​

History of OpenGL

https://www.khronos.org/opengl/wiki/History_of_OpenGL​

Anton's OpenGL 4 Tutorials

https://antongerdelan.net/opengl/​

OpenGL Wikipedia

https://es.wikipedia.org/wiki/OpenGL

and who can forget NEHE Tutorials

https://nehe.gamedev.net/

fleabay: i hope you dont have thinked much for reach that conclussion

i said cos was a referencing on OGL stuff, buy anyways, much of things people think are obsolete can be “updated or re-coded with minimal changes” ….. i know some people say C/C++ is obsolete too :D ….. o yes Python is better how i dont fall in that before hahahaha :D