### 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.
bool is_tooltip_shown = false;
				if (gui.tooltip_popup) {
					if (gui.tooltip_control) {
						String tooltip = _gui_get_tooltip(over, gui.tooltip_control->get_global_transform().xform_inv(mpos));
						tooltip = tooltip.strip_edges();
						if (tooltip.length() == 0) {
							_gui_cancel_tooltip();
						} else if (gui.tooltip_label) {
							if (tooltip == gui.tooltip_label->get_text()) {
								is_tooltip_shown = true;
							}
						} else {
							is_tooltip_shown = true; 
						}
					} else {
						_gui_cancel_tooltip();
					}
				}
				if (!is_tooltip_shown && over->can_process()) {
					if (gui.tooltip_timer.is_valid()) {
						gui.tooltip_timer->release_connections();
						gui.tooltip_timer = Ref<SceneTreeTimer>();
					}
					gui.tooltip_control = over;
					gui.tooltip_pos = over->get_screen_transform().xform(pos);
					gui.tooltip_timer = get_tree()->create_timer(gui.tooltip_delay);
					gui.tooltip_timer->set_ignore_time_scale(true);
					gui.tooltip_timer->connect("timeout", callable_mp(this, &Viewport::_gui_show_tooltip));
				}
			}