I have successfully downloaded and tried out GLFW after considering many positive comments on the internets from several sources, but things do not look that good after inspecting the examples and the provided guideline for GLFW.
The OpenGL specific functions used in the examples are basically deprecated or completely removed from the modern OpenGL approach, glbegin() and glend() kinda reminds me of OpenGL 2.0 ( not OpenGL ES, just OpenGL ) and surely it's not the proper way of doing things with OpenGL 3.x or 4.x .
Now I'm asking: what are the contexts really compatibles with GLFW ? Why not removing that examples that are just wrong ? According to what I'm seeing I will say that GLFW it's a framework for the really old OpenGL contexts like 2.x with the fixed pipeline.
GLFW can create a context for any available version of OpenGL, as is stated on the website and in the documentation. However, the examples were written a long time ago and so use the versions of OpenGL common at that time. New examples are welcome.