### Godot version

4.0.3.stable

### System information

Windows 10/11

### Issue description

I want the player's cursor to change when highlighting pickable Area2Ds; to do this, I have the areas modify the `mouse_default_cursor_shape` property on an external Control when the mouse enters or exits. If another Control appears in front of the Area2D while the mouse is over it, there is a chance that the project will crash.

Nothing prints to the IDE's output on this crash. If running the editor with console, then
```
ERROR: Condition "slot >= slot_max" is true. Returning: nullptr
   at: get_instance (./core/object/object.h:972)
```
will sometimes appear alongside the crash. If it appears, it always appears twice.

When I run a debug build of the editor through WinDbg, WinDbg will catch the following exception:
```
(3b58.2aac): Access violation - code c0000005 (!!! second chance !!!)
godot_windows_editor_x86_64!ObjectDB::get_instance [inlined in godot_windows_editor_x86_64!Viewport::_cleanup_mouseover_colliders+0x6f]:
00007ff6`ac254a1f 488b5310        mov     rdx,qword ptr [rbx+10h] ds:cccccccc`c31c419b=????????????????
```
When using this method, the exception is not random; it always occurs on the first attempt.

### Steps to reproduce

- Open the minimal reproduction project in the editor.
- Run the project.
- Click on the Area2D (you'll want visible collision shapes on).
- A full-screen button will pop up. If the game does not crash at this point, clicking the button will hide it so you can try again. It should crash within a few seconds of mashing.

### Minimal reproduction project

[Crash Test.zip](https://github.com/godotengine/godot/files/12027772/Crash.Test.zip)

}
		Control *over = nullptr;
		if (gui.mouse_focus) {
			over = gui.mouse_focus;
		} else if (gui.mouse_in_viewport) {
			over = gui_find_control(mpos);
		}
		DisplayServer::CursorShape ds_cursor_shape = (DisplayServer::CursorShape)Input::get_singleton()->get_default_cursor_shape();
		if (over) {
			Transform2D localizer = over->get_global_transform_with_canvas().affine_inverse();
			Size2 pos = localizer.xform(mpos);
			Vector2 velocity = localizer.basis_xform(mm->get_velocity());
			Vector2 rel = localizer.basis_xform(mm->get_relative());
			mm = mm->xformed_by(Transform2D()); 
			mm->set_global_position(mpos);
			mm->set_velocity(velocity);
			mm->set_relative(rel);
			if (mm->get_button_mask().is_empty()) {
				
				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;
							}