### 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)

#ifndef _3D_DISABLED
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "audio_listener_enable_3d"), "set_as_audio_listener_3d", "is_audio_listener_3d");
#endif
	ADD_GROUP("Physics", "physics_");
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "physics_object_picking"), "set_physics_object_picking", "get_physics_object_picking");
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "physics_object_picking_sort"), "set_physics_object_picking_sort", "get_physics_object_picking_sort");
	ADD_GROUP("GUI", "gui_");
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "gui_disable_input"), "set_disable_input", "is_input_disabled");
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "gui_snap_controls_to_pixels"), "set_snap_controls_to_pixels", "is_snap_controls_to_pixels_enabled");
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "gui_embed_subwindows"), "set_embedding_subwindows", "is_embedding_subwindows");
	ADD_GROUP("SDF", "sdf_");
	ADD_PROPERTY(PropertyInfo(Variant::INT, "sdf_oversize", PROPERTY_HINT_ENUM, "100%,120%,150%,200%"), "set_sdf_oversize", "get_sdf_oversize");
	ADD_PROPERTY(PropertyInfo(Variant::INT, "sdf_scale", PROPERTY_HINT_ENUM, "100%,50%,25%"), "set_sdf_scale", "get_sdf_scale");
	ADD_GROUP("Positional Shadow Atlas", "positional_shadow_atlas_");
	ADD_PROPERTY(PropertyInfo(Variant::INT, "positional_shadow_atlas_size"), "set_positional_shadow_atlas_size", "get_positional_shadow_atlas_size");
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "positional_shadow_atlas_16_bits"), "set_positional_shadow_atlas_16_bits", "get_positional_shadow_atlas_16_bits");
	ADD_PROPERTYI(PropertyInfo(Variant::INT, "positional_shadow_atlas_quad_0", PROPERTY_HINT_ENUM, "Disabled,1 Shadow,4 Shadows,16 Shadows,64 Shadows,256 Shadows,1024 Shadows"), "set_positional_shadow_atlas_quadrant_subdiv", "get_positional_shadow_atlas_quadrant_subdiv", 0);
	ADD_PROPERTYI(PropertyInfo(Variant::INT, "positional_shadow_atlas_quad_1", PROPERTY_HINT_ENUM, "Disabled,1 Shadow,4 Shadows,16 Shadows,64 Shadows,256 Shadows,1024 Shadows"), "set_positional_shadow_atlas_quadrant_subdiv", "get_positional_shadow_atlas_quadrant_subdiv", 1);
	ADD_PROPERTYI(PropertyInfo(Variant::INT, "positional_shadow_atlas_quad_2", PROPERTY_HINT_ENUM, "Disabled,1 Shadow,4 Shadows,16 Shadows,64 Shadows,256 Shadows,1024 Shadows"), "set_positional_shadow_atlas_quadrant_subdiv", "get_positional_shadow_atlas_quadrant_subdiv", 2);
	ADD_PROPERTYI(PropertyInfo(Variant::INT, "positional_shadow_atlas_quad_3", PROPERTY_HINT_ENUM, "Disabled,1 Shadow,4 Shadows,16 Shadows,64 Shadows,256 Shadows,1024 Shadows"), "set_positional_shadow_atlas_quadrant_subdiv", "get_positional_shadow_atlas_quadrant_subdiv", 3);
	ADD_PROPERTY(PropertyInfo(Variant::TRANSFORM2D, "canvas_transform", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_NONE), "set_canvas_transform", "get_canvas_transform");
	ADD_PROPERTY(PropertyInfo(Variant::TRANSFORM2D, "global_canvas_transform", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_NONE), "set_global_canvas_transform", "get_global_canvas_transform");
	ADD_PROPERTY(PropertyInfo(Variant::INT, "canvas_cull_mask", PROPERTY_HINT_LAYERS_2D_RENDER), "set_canvas_cull_mask", "get_canvas_cull_mask");
	ADD_SIGNAL(MethodInfo("size_changed"));
	ADD_SIGNAL(MethodInfo("gui_focus_changed", PropertyInfo(Variant::OBJECT, "node", PROPERTY_HINT_RESOURCE_TYPE, "Control")));
	BIND_ENUM_CONSTANT(SHADOW_ATLAS_QUADRANT_SUBDIV_DISABLED);
	BIND_ENUM_CONSTANT(SHADOW_ATLAS_QUADRANT_SUBDIV_1);
	BIND_ENUM_CONSTANT(SHADOW_ATLAS_QUADRANT_SUBDIV_4);
	BIND_ENUM_CONSTANT(SHADOW_ATLAS_QUADRANT_SUBDIV_16);
	BIND_ENUM_CONSTANT(SHADOW_ATLAS_QUADRANT_SUBDIV_64);