### 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
bool use_msaa = render_buffers->get_msaa_3d() != RS::VIEWPORT_MSAA_DISABLED;
	RID specular = render_buffers->get_texture(RB_SCOPE_FORWARD_CLUSTERED, use_msaa ? RB_TEX_SPECULAR_MSAA : RB_TEX_SPECULAR);
	return FramebufferCacheRD::get_singleton()->get_cache_multiview(render_buffers->get_view_count(), specular);
}
void RenderForwardClustered::setup_render_buffer_data(Ref<RenderSceneBuffersRD> p_render_buffers) {
	Ref<RenderBufferDataForwardClustered> data;
	data.instantiate();
	p_render_buffers->set_custom_data(RB_SCOPE_FORWARD_CLUSTERED, data);
	Ref<RendererRD::GI::RenderBuffersGI> rbgi;
	rbgi.instantiate();
	p_render_buffers->set_custom_data(RB_SCOPE_GI, rbgi);
}
bool RenderForwardClustered::free(RID p_rid) {
	if (RendererSceneRenderRD::free(p_rid)) {
		return true;
	}
	return false;
}
template <RenderForwardClustered::PassMode p_pass_mode, uint32_t p_color_pass_flags>
void RenderForwardClustered::_render_list_template(RenderingDevice::DrawListID p_draw_list, RenderingDevice::FramebufferFormatID p_framebuffer_Format, RenderListParameters *p_params, uint32_t p_from_element, uint32_t p_to_element) {