The following error persists when you try to output a color using:-
#version 330 core
in vec3 fragmentColor;
in vec2 fragmentTexCoord;
uniform sampler2D imageTexture;
out vec4 color;
void main()
{ color = vec4(1.0); // White color }
// Should've produce white screen
In short, you cant get an output rather than the texture fed to the shader (the screen).
It worked in previous versions