### 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
Color(0, 0, 0, 0)
		};
		RD::DrawListID draw_list = RD::get_singleton()->draw_list_begin(p_framebuffer, RD::INITIAL_ACTION_CLEAR, RD::FINAL_ACTION_READ, RD::INITIAL_ACTION_CLEAR, RD::FINAL_ACTION_READ, clear, 1.0, 0, p_region);
		const int uv_offset_count = 9;
		static const Vector2 uv_offsets[uv_offset_count] = {
			Vector2(-1, 1),
			Vector2(1, 1),
			Vector2(1, -1),
			Vector2(-1, -1),
			Vector2(-1, 0),
			Vector2(1, 0),
			Vector2(0, -1),
			Vector2(0, 1),
			Vector2(0, 0),
		};
		for (int i = 0; i < uv_offset_count; i++) {
			Vector2 ofs = uv_offsets[i];
			ofs.x /= p_region.size.width;
			ofs.y /= p_region.size.height;
			render_list_params.uv_offset = ofs;
			_render_list(draw_list, RD::get_singleton()->framebuffer_get_format(p_framebuffer), &render_list_params, 0, render_list_params.element_count); 
		}
		render_list_params.uv_offset = Vector2();
		render_list_params.force_wireframe = false;
		_render_list(draw_list, RD::get_singleton()->framebuffer_get_format(p_framebuffer), &render_list_params, 0, render_list_params.element_count); 
		RD::get_singleton()->draw_list_end();
	}
	RD::get_singleton()->draw_command_end_label();
}
void RenderForwardClustered::_render_sdfgi(Ref<RenderSceneBuffersRD> p_render_buffers, const Vector3i &p_from, const Vector3i &p_size, const AABB &p_bounds, const PagedArray<RenderGeometryInstance *> &p_instances, const RID &p_albedo_texture, const RID &p_emission_texture, const RID &p_emission_aniso_texture, const RID &p_geom_facing_texture, float p_exposure_normalization) {