The documentation of
glFramebufferRenderbuffer only says that
renderbuffertarget needs to be
GL_RENDERBUFFER, though it does not specify that the attached renderbuffer, that is also given to the function, needs to be bound to
I deem it not having to be so, because why would I have to specify the renderbuffer again if it should be bound beforehand?
Especially since the glNamedFramebufferRenderbuffer was introduced, it should not be nesseccary to bind anything.