### Godot version

4.0.2 stable

### System information

issue tested on win10 with ryzen 7 and rx 6600, win11 with ryzen 7 and gtx 3050

### Issue description

When creating a screen reading post processing shader, the normal buffer functions correctly in the editor, but does not seem to be functioning as expected in debug, producing only a solid colour when run. I am unsure if this behaviour is intended, but if so, I feel it should be properly documented.

Running correctly in editor:
![image](https://user-images.githubusercontent.com/71034402/230672620-fc5e4baf-c12e-4755-b7a2-206087459307.png)

Solid colour in debug:
![image](https://user-images.githubusercontent.com/71034402/230672489-d9c29755-c2d3-4e72-9ea0-355148e916fe.png)


### Steps to reproduce

*this shader should be attached to a MeshInstance3D quadmesh*
minimal shader to reproduce:

```glsl
shader_type spatial;
render_mode unshaded, cull_disabled;

uniform sampler2D NORMAL_TEXTURE : hint_normal_roughness_texture, filter_linear_mipmap;

void vertex(){
	VERTEX *= 2.0;
	POSITION = vec4(VERTEX, 1.0);
}

void fragment(){
	ALBEDO = texture(NORMAL_TEXTURE, SCREEN_UV).rgb;
}
```

### Minimal reproduction project

N/A
}
	
	if (light_storage->owns_reflection_probe_instance(p_render_data->reflection_probe)) {
		current_cluster_builder = light_storage->reflection_probe_instance_get_cluster_builder(p_render_data->reflection_probe, &cluster_builder_shared);
		if (p_render_data->camera_attributes.is_valid()) {
			light_storage->reflection_probe_set_baked_exposure(light_storage->reflection_probe_instance_get_probe(p_render_data->reflection_probe), RSG::camera_attributes->camera_attributes_get_exposure_normalization_factor(p_render_data->camera_attributes));
		}
	} else if (rb_data.is_valid()) {
		current_cluster_builder = rb_data->cluster_builder;
		p_render_data->voxel_gi_count = 0;
		if (rb->has_custom_data(RB_SCOPE_SDFGI)) {
			Ref<RendererRD::GI::SDFGI> sdfgi = rb->get_custom_data(RB_SCOPE_SDFGI);
			if (sdfgi.is_valid()) {
				sdfgi->update_cascades();
				sdfgi->pre_process_gi(p_render_data->scene_data->cam_transform, p_render_data);
				sdfgi->update_light();
			}
		}
		gi.setup_voxel_gi_instances(p_render_data, p_render_data->render_buffers, p_render_data->scene_data->cam_transform, *p_render_data->voxel_gi_instances, p_render_data->voxel_gi_count);
	} else {
		ERR_PRINT("No render buffer nor reflection atlas, bug"); 
		current_cluster_builder = nullptr;
	}
	if (current_cluster_builder != nullptr) {
		p_render_data->cluster_buffer = current_cluster_builder->get_cluster_buffer();
		p_render_data->cluster_size = current_cluster_builder->get_cluster_size();
		p_render_data->cluster_max_elements = current_cluster_builder->get_max_cluster_elements();
	}
	_update_vrs(rb);
	RENDER_TIMESTAMP("Setup 3D Scene");