### Godot version

4.0.dev (c309de53997feff3286295fb2d71657f112a15db)

### System information

Linux, Nvidia, Vulkan

### Issue description

Editor segfaults when certain conditions are met when using the AnimationPlayer editor.

### Steps to reproduce

1. Create multiple animations, saved into a animation collection
2. Open an existing animation, then make a new empty animation
3. Change from seconds to fps, or add a new property to animate ()
4. Editor crashes

NOTE: It is slightly random and I have not found a perfect repro

### Minimal reproduction project

N/A (TBD?)
if (get_script_instance()) {
		return Object::cast_to<AnimationTrackEdit>(get_script_instance()->call("create_audio_track_edit").operator Object *());
	}
	return nullptr;
}
AnimationTrackEdit *AnimationTrackEditPlugin::create_animation_track_edit(Object *p_object) {
	if (get_script_instance()) {
		return Object::cast_to<AnimationTrackEdit>(get_script_instance()->call("create_animation_track_edit", p_object).operator Object *());
	}
	return nullptr;
}
void AnimationTrackEditGroup::_notification(int p_what) {
	switch (p_what) {
		case NOTIFICATION_DRAW: {
			Ref<Font> font = get_theme_font(SNAME("font"), SNAME("Label"));
			int font_size = get_theme_font_size(SNAME("font_size"), SNAME("Label"));
			int separation = get_theme_constant(SNAME("h_separation"), SNAME("ItemList"));
			Color color = get_theme_color(SNAME("font_color"), SNAME("Label"));
			if (root && root->has_node(node)) {
				Node *n = root->get_node(node);
				if (n && EditorNode::get_singleton()->get_editor_selection()->is_selected(n)) {
					color = get_theme_color(SNAME("accent_color"), SNAME("Editor"));