### 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
bool all_saved = true;
	for (int i = 0; i < editor_data.get_edited_scene_count(); i++) {
		Node *scene = editor_data.get_edited_scene_root(i);
		if (scene) {
			if (!scene->get_scene_file_path().is_empty() && DirAccess::exists(scene->get_scene_file_path().get_base_dir())) {
				if (i != editor_data.get_edited_scene()) {
					_save_scene(scene->get_scene_file_path(), i);
				} else {
					_save_scene_with_preview(scene->get_scene_file_path());
				}
			} else if (!scene->get_scene_file_path().is_empty()) {
				all_saved = false;
			}
		}
	}
	if (!all_saved) {
		show_warning(TTR("Could not save one or more scenes!"), TTR("Save All Scenes"));
	}
	save_default_environment();
}
void EditorNode::_mark_unsaved_scenes() {