### 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)

if (mm.is_valid() && mm->get_device() == InputEvent::DEVICE_ID_INTERNAL) {
										send_event = false;
									}
								}
								HashMap<Pair<ObjectID, int>, uint64_t, PairHash<ObjectID, int>>::Iterator SF = physics_2d_shape_mouseover.find(Pair(res[i].collider_id, res[i].shape));
								if (!SF) {
									physics_2d_shape_mouseover.insert(Pair(res[i].collider_id, res[i].shape), frame);
									co->_mouse_shape_enter(res[i].shape);
								} else {
									SF->value = frame;
								}
							}
							if (send_event) {
								co->_input_event_call(this, ev, res[i].shape);
							}
						}
					}
				}
			}
			if (is_mouse) {
				_cleanup_mouseover_colliders(false, false, frame);
			}
		}
#ifndef _3D_DISABLED
		CollisionObject3D *capture_object = nullptr;
		if (physics_object_capture.is_valid()) {
			capture_object = Object::cast_to<CollisionObject3D>(ObjectDB::get_instance(physics_object_capture));
			if (!capture_object || !camera_3d || (mb.is_valid() && mb->get_button_index() == MouseButton::LEFT && !mb->is_pressed())) {
				physics_object_capture = ObjectID();