### 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
root_name = EditorNode::adjust_scene_name_casing(root_name);
				file->set_current_path(root_name + "." + extensions.front()->get().to_lower());
			}
			file->popup_file_dialog();
			file->set_title(TTR("Save Scene As..."));
		} break;
		case FILE_SAVE_ALL_SCENES: {
			_save_all_scenes();
		} break;
		case FILE_RUN_SCENE: {
			project_run_bar->play_current_scene();
		} break;
		case FILE_EXPORT_PROJECT: {
			project_export->popup_export();
		} break;
		case FILE_EXTERNAL_OPEN_SCENE: {
			if (unsaved_cache && !p_confirmed) {
				confirmation->set_ok_button_text(TTR("Open"));
				confirmation->set_text(TTR("Current scene not saved. Open anyway?"));
				confirmation->popup_centered();
				break;
			}
			bool oprev = opening_prev;
			Error err = load_scene(external_file);
			if (err == OK && oprev) {
				previous_scenes.pop_back();
				opening_prev = false;
			}
		} break;
		case EDIT_UNDO: {