### 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
file_menu->set_item_disabled(file_menu->get_item_index(FILE_OPEN_PREV), previous_scenes.is_empty());
	_update_undo_redo_allowed();
}
void EditorNode::_update_file_menu_closed() {
	file_menu->set_item_disabled(file_menu->get_item_index(FILE_OPEN_PREV), false);
}
VBoxContainer *EditorNode::get_main_screen_control() {
	return main_screen_vbox;
}
void EditorNode::editor_select(int p_which) {
	static bool selecting = false;
	if (selecting || changing_scene) {
		return;
	}
	ERR_FAIL_INDEX(p_which, editor_table.size());
	if (!main_editor_buttons[p_which]->is_visible()) { 
		return;
	}
	selecting = true;
	for (int i = 0; i < main_editor_buttons.size(); i++) {
		main_editor_buttons[i]->set_pressed(i == p_which);
	}
	selecting = false;
	EditorPlugin *new_editor = editor_table[p_which];
	ERR_FAIL_NULL(new_editor);
	if (editor_plugin_screen == new_editor) {
		return;