### Godot version

Godot Engine v4.0.beta16.official.518b9e580

### System information

Linux, Vulkan, nvidia RTX 2070, Driver 525.60.11

### Issue description

Editor crashes when changing between theme editor and animation editor

Console:
`ERROR: Condition "slot >= slot_max" is true. Returning: nullptr
   at: get_instance (./core/object/object.h:962)
ERROR: Condition "slot >= slot_max" is true. Returning: nullptr
   at: get_instance (./core/object/object.h:962)

================================================================
handle_crash: Program crashed with signal 11
Engine version: Godot Engine v4.0.beta16.official (518b9e5801a19229805fe837d7d0cf92920ad413)
Dumping the backtrace. Please include this when reporting the bug to the project developer.
[1] /lib/x86_64-linux-gnu/libc.so.6(+0x42520) [0x7f908134c520] (??:0)
[2] /home/solorvox/GameDev/godot-engine/Godot_v4.0-beta16_linux.x86_64() [0x1c6d494] (??:0)
[3] /home/solorvox/GameDev/godot-engine/Godot_v4.0-beta16_linux.x86_64() [0x1c4eefe] (??:0)
[4] /home/solorvox/GameDev/godot-engine/Godot_v4.0-beta16_linux.x86_64() [0x44fb21a] (??:0)
[5] /home/solorvox/GameDev/godot-engine/Godot_v4.0-beta16_linux.x86_64() [0x26faf8b] (??:0)
[6] /home/solorvox/GameDev/godot-engine/Godot_v4.0-beta16_linux.x86_64() [0x448c994] (??:0)
[7] /home/solorvox/GameDev/godot-engine/Godot_v4.0-beta16_linux.x86_64() [0x2a9eb11] (??:0)
[8] /home/solorvox/GameDev/godot-engine/Godot_v4.0-beta16_linux.x86_64() [0x2a9eb8f] (??:0)
[9] /home/solorvox/GameDev/godot-engine/Godot_v4.0-beta16_linux.x86_64() [0x1c65ae0] (??:0)
[10] /home/solorvox/GameDev/godot-engine/Godot_v4.0-beta16_linux.x86_64() [0x42e50c2] (??:0)
[11] /home/solorvox/GameDev/godot-engine/Godot_v4.0-beta16_linux.x86_64() [0x44fb21a] (??:0)
[12] /home/solorvox/GameDev/godot-engine/Godot_v4.0-beta16_linux.x86_64() [0x2bcf06f] (??:0)
[13] /home/solorvox/GameDev/godot-engine/Godot_v4.0-beta16_linux.x86_64() [0x2bcfa7e] (??:0)
[14] /home/solorvox/GameDev/godot-engine/Godot_v4.0-beta16_linux.x86_64() [0x2b30f15] (??:0)
[15] /home/solorvox/GameDev/godot-engine/Godot_v4.0-beta16_linux.x86_64() [0x2b817d5] (??:0)
[16] /home/solorvox/GameDev/godot-engine/Godot_v4.0-beta16_linux.x86_64() [0x2b85781] (??:0)
[17] /home/solorvox/GameDev/godot-engine/Godot_v4.0-beta16_linux.x86_64() [0x2b85deb] (??:0)
[18] /home/solorvox/GameDev/godot-engine/Godot_v4.0-beta16_linux.x86_64() [0x2ba1cf5] (??:0)
[19] /home/solorvox/GameDev/godot-engine/Godot_v4.0-beta16_linux.x86_64() [0xe69114] (??:0)
[20] /home/solorvox/GameDev/godot-engine/Godot_v4.0-beta16_linux.x86_64() [0x42d5f34] (??:0)
[21] /home/solorvox/GameDev/godot-engine/Godot_v4.0-beta16_linux.x86_64() [0x42d6db5] (??:0)
[22] /home/solorvox/GameDev/godot-engine/Godot_v4.0-beta16_linux.x86_64() [0xe6ab2d] (??:0)
[23] /home/solorvox/GameDev/godot-engine/Godot_v4.0-beta16_linux.x86_64() [0xddd7c2] (??:0)
[24] /lib/x86_64-linux-gnu/libc.so.6(+0x29d90) [0x7f9081333d90] (??:0)
[25] /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0x80) [0x7f9081333e40] (??:0)
[26] /home/solorvox/GameDev/godot-engine/Godot_v4.0-beta16_linux.x86_64() [0xdfd8ee] (??:0)
-- END OF BACKTRACE --
================================================================`


### Steps to reproduce

Open included project
1) Click on AnimationPlayer in scene tree
2) Click on TextureRect in scene tree
4) Click on "Theme" editor at bottom of editor window (theme editor opens)
5) Click on "Animation" editor at bottom (crash)

Notes: The shader source code must be open, and a theme must be open to repeat this crash

### Minimal reproduction project

[animation-crash.zip](https://github.com/godotengine/godot/files/10530646/animation-crash.zip)

bool waiting_for_first_scan = true;
	int current_menu_option = 0;
	SubViewport *scene_root = nullptr; 
	Object *current = nullptr;
	Ref<Resource> saving_resource;
	uint64_t update_spinner_step_msec = 0;
	uint64_t update_spinner_step_frame = 0;
	int update_spinner_step = 0;
	String _tmp_import_path;
	String external_file;
	String open_navigate;
	String run_custom_filename;
	String run_current_filename;
	DynamicFontImportSettings *fontdata_import_settings = nullptr;
	SceneImportSettings *scene_import_settings = nullptr;
	AudioStreamImportSettings *audio_stream_import_settings = nullptr;
	String import_reload_fn;
	HashSet<String> textfile_extensions;
	HashSet<FileDialog *> file_dialogs;
	HashSet<EditorFileDialog *> editor_file_dialogs;
	Vector<Ref<EditorResourceConversionPlugin>> resource_conversion_plugins;
	PrintHandlerList print_handler;
	HashMap<String, Ref<Texture2D>> icon_type_cache;
	HashMap<Ref<Script>, Ref<Texture>> script_icon_cache;
	static EditorBuildCallback build_callbacks[MAX_BUILD_CALLBACKS];
	static EditorPluginInitializeCallback plugin_init_callbacks[MAX_INIT_CALLBACKS];
	static int build_callback_count;
	static int plugin_init_callback_count;
	static Vector<EditorNodeInitCallback> _init_callbacks;
	static void _dependency_error_report(void *ud, const String &p_path, const String &p_dep, const String &p_type) {