### 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
p_render_data->directional_light_count = directional_light_count;
	if (current_cluster_builder) {
		current_cluster_builder->bake_cluster();
	}
	if (rb_data.is_valid()) {
		bool directional_shadows = RendererRD::LightStorage::get_singleton()->has_directional_shadows(directional_light_count);
		_update_volumetric_fog(rb, p_render_data->environment, p_render_data->scene_data->cam_projection, p_render_data->scene_data->cam_transform, p_render_data->scene_data->prev_cam_transform.affine_inverse(), p_render_data->shadow_atlas, directional_light_count, directional_shadows, positional_light_count, p_render_data->voxel_gi_count, *p_render_data->fog_volumes);
	}
}
void RenderForwardClustered::_process_ssr(Ref<RenderSceneBuffersRD> p_render_buffers, RID p_dest_framebuffer, const RID *p_normal_slices, RID p_specular_buffer, const RID *p_metallic_slices, RID p_environment, const Projection *p_projections, const Vector3 *p_eye_offsets, bool p_use_additive) {
	ERR_FAIL_NULL(ss_effects);
	ERR_FAIL_COND(p_render_buffers.is_null());
	Ref<RenderBufferDataForwardClustered> rb_data = p_render_buffers->get_custom_data(RB_SCOPE_FORWARD_CLUSTERED);
	ERR_FAIL_COND(rb_data.is_null());
	Size2i internal_size = p_render_buffers->get_internal_size();
	bool can_use_effects = internal_size.x >= 8 && internal_size.y >= 8;
	uint32_t view_count = p_render_buffers->get_view_count();
	if (!can_use_effects) {
		
		copy_effects->merge_specular(p_dest_framebuffer, p_specular_buffer, p_use_additive ? RID() : p_render_buffers->get_internal_texture(), RID(), view_count);
		return;
	}
	ERR_FAIL_COND(p_environment.is_null());
	ERR_FAIL_COND(!environment_get_ssr_enabled(p_environment));
	ss_effects->ssr_allocate_buffers(p_render_buffers, rb_data->ss_effects_data.ssr, _render_buffers_get_color_format());
	ss_effects->screen_space_reflection(p_render_buffers, rb_data->ss_effects_data.ssr, p_normal_slices, p_metallic_slices, environment_get_ssr_max_steps(p_environment), environment_get_ssr_fade_in(p_environment), environment_get_ssr_fade_out(p_environment), environment_get_ssr_depth_tolerance(p_environment), p_projections, p_eye_offsets);
	RID output = p_render_buffers->get_texture(RB_SCOPE_SSR, RB_OUTPUT);
	copy_effects->merge_specular(p_dest_framebuffer, p_specular_buffer, p_use_additive ? RID() : p_render_buffers->get_internal_texture(), output, view_count);
}
void RenderForwardClustered::_process_sss(Ref<RenderSceneBuffersRD> p_render_buffers, const Projection &p_camera) {