Sets whether the `GdkGLContext` should be forward-compatible.
Forward-compatible contexts must not support OpenGL functionality that has been marked as deprecated in the requested version; non-forward compatible contexts, on the other hand, must support both deprecated and non deprecated functionality.
The `GdkGLContext` must not be realized or made current prior to calling this function.
this |
a `GdkGLContext` |
compatible |
whether the context should be forward-compatible |