### Godot version

master

### System information

Godot v4.2.beta (0ea75d77c) - Windows 10.0.22621 - Vulkan (Forward+) - dedicated NVIDIA GeForce RTX 2070 (NVIDIA; 31.0.15.3598) - Intel(R) Core(TM) i7-10750H CPU @ 2.60GHz (12 Threads)

### Issue description

When any of the Import, Filesystem, Node, or History docks are floating, changing an editor feature crashes the engine.
Changing any setting or selecting a different profile triggers it.

This is because `EditorNode::_feature_profile_changed` assumes the docks are in a `TabContainer`, and if they are floating they aren't in one.


### Steps to reproduce

Make any of these docks floating: Import, Filesystem, Node, or History
Open Editor Features (Editor -> Manage Editor Features...)
Make a profile (if you have none) or change a setting on the existing profile

### Minimal reproduction project

n/a
_save_external_resources();
	saving_scene = p_file; 
	editor_data.save_editor_external_data();
	saving_scene = "";
	for (Pair<AnimationMixer *, Ref<AnimatedValuesBackup>> &E : anim_backups) {
		E.first->restore(E.second);
	}
	if (err == OK) {
		scene->set_scene_file_path(ProjectSettings::get_singleton()->localize_path(p_file));
		editor_data.set_scene_as_saved(idx);
		editor_data.set_scene_modified_time(idx, FileAccess::get_modified_time(p_file));
		editor_folding.save_scene_folding(scene, p_file);
		_update_title();
		scene_tabs->update_scene_tabs();
	} else {
		_dialog_display_save_error(p_file, err);
	}
	scene->propagate_notification(NOTIFICATION_EDITOR_POST_SAVE);
}
void EditorNode::save_all_scenes() {
	project_run_bar->stop_playing();
	_save_all_scenes();
}
void EditorNode::save_scene_if_open(const String &p_scene_path) {
	int idx = editor_data.get_edited_scene_from_path(p_scene_path);
	if (idx >= 0) {
		_save_scene(p_scene_path, idx);
	}
}
void EditorNode::save_scene_list(const HashSet<String> &p_scene_paths) {