### Godot version

4.0.3-stable

### System information

Windows 10

### Issue description

In some projects ViewportTexture remains pink and doesn't render viewport content after upgrading from 4.0.2-stable to 4.0.3-stable. If a pair of files viewport.h/viewport.cpp are downgraded back to what they were in 4.0.2-stable, problem goes away.

This is how it looks in 4.0.3-stable:
![4 0 3_stable_viewport_4 0 3](https://github.com/godotengine/godot/assets/1449921/44c191a9-4b67-4b02-90b6-4ab615f62a73)

And this is how it looks if viewport.h/viewport.cpp are downgraded back to what they were in 4.0.2-stable.
![4 0 3_stable_viewport_4 0 2](https://github.com/godotengine/godot/assets/1449921/f5abc605-f129-4222-9c0e-e9a07621dd9d)



### Steps to reproduce

Unfortunately, I cannot come up wit a simple demo project reproducing the problem. It exists in some projects and doesn't exist in others.


### Minimal reproduction project

Cannot produce a simple project reproducing the problem. In simple projects it works fine.
set_positional_shadow_atlas_quadrant_subdiv(1, SHADOW_ATLAS_QUADRANT_SUBDIV_4);
	set_positional_shadow_atlas_quadrant_subdiv(2, SHADOW_ATLAS_QUADRANT_SUBDIV_16);
	set_positional_shadow_atlas_quadrant_subdiv(3, SHADOW_ATLAS_QUADRANT_SUBDIV_64);
	set_mesh_lod_threshold(mesh_lod_threshold);
	String id = itos(get_instance_id());
	input_group = "_vp_input" + id;
	gui_input_group = "_vp_gui_input" + id;
	unhandled_input_group = "_vp_unhandled_input" + id;
	shortcut_input_group = "_vp_shortcut_input" + id;
	unhandled_key_input_group = "_vp_unhandled_key_input" + id;
	// Window tooltip.
	gui.tooltip_delay = GLOBAL_DEF(PropertyInfo(Variant::FLOAT, "gui/timers/tooltip_delay_sec", PROPERTY_HINT_RANGE, "0,5,0.01,or_greater"), 0.5);
#ifndef _3D_DISABLED
	set_scaling_3d_mode((Viewport::Scaling3DMode)(int)GLOBAL_GET("rendering/scaling_3d/mode"));
	set_scaling_3d_scale(GLOBAL_GET("rendering/scaling_3d/scale"));
	set_fsr_sharpness((float)GLOBAL_GET("rendering/scaling_3d/fsr_sharpness"));
	set_texture_mipmap_bias((float)GLOBAL_GET("rendering/textures/default_filters/texture_mipmap_bias"));
#endif 
	set_sdf_oversize(sdf_oversize); // Set to server.
}
Viewport::~Viewport() {
	// Erase itself from viewport textures.
	for (ViewportTexture *E : viewport_textures) {
		E->vp = nullptr;
	}
	ERR_FAIL_NULL(RenderingServer::get_singleton());
	RenderingServer::get_singleton()->free(viewport);
}
//
void SubViewport::set_size(const Size2i &p_size) {