### 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.
ERR_MAIN_THREAD_GUARD;
	
	
	
	scaling_3d_scale = CLAMP(p_scaling_3d_scale, 0.1, 2.0);
	RS::get_singleton()->viewport_set_scaling_3d_scale(viewport, scaling_3d_scale);
}
float Viewport::get_scaling_3d_scale() const {
	ERR_READ_THREAD_GUARD_V(0);
	return scaling_3d_scale;
}
void Viewport::set_fsr_sharpness(float p_fsr_sharpness) {
	ERR_MAIN_THREAD_GUARD;
	if (fsr_sharpness == p_fsr_sharpness) {
		return;
	}
	if (p_fsr_sharpness < 0.0f) {
		p_fsr_sharpness = 0.0f;
	}
	fsr_sharpness = p_fsr_sharpness;
	RS::get_singleton()->viewport_set_fsr_sharpness(viewport, p_fsr_sharpness);
}
float Viewport::get_fsr_sharpness() const {
	ERR_READ_THREAD_GUARD_V(0);
	return fsr_sharpness;
}
void Viewport::set_texture_mipmap_bias(float p_texture_mipmap_bias) {