### 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
node_tc->set_themes(editor_themes);
	} else {
		ThemeDB::get_singleton()->create_theme_context(this, editor_themes);
	}
	Window *window = get_window();
	if (window) {
		ThemeContext *window_tc = ThemeDB::get_singleton()->get_theme_context(window);
		if (window_tc) {
			window_tc->set_themes(editor_themes);
		} else {
			ThemeDB::get_singleton()->create_theme_context(window, editor_themes);
		}
	}
	if (CanvasItemEditor::get_singleton()->get_theme_preview() == CanvasItemEditor::THEME_PREVIEW_EDITOR) {
		update_preview_themes(CanvasItemEditor::THEME_PREVIEW_EDITOR);
	}
	gui_base->add_theme_style_override("panel", theme->get_stylebox(SNAME("Background"), EditorStringName(EditorStyles)));
	main_vbox->set_anchors_and_offsets_preset(Control::PRESET_FULL_RECT, Control::PRESET_MODE_MINSIZE, theme->get_constant(SNAME("window_border_margin"), EditorStringName(Editor)));
	main_vbox->add_theme_constant_override("separation", theme->get_constant(SNAME("top_bar_separation"), EditorStringName(Editor)));
	scene_root_parent->add_theme_style_override("panel", theme->get_stylebox(SNAME("Content"), EditorStringName(EditorStyles)));
	bottom_panel->add_theme_style_override("panel", theme->get_stylebox(SNAME("BottomPanel"), EditorStringName(EditorStyles)));
	main_menu->add_theme_style_override("hover", theme->get_stylebox(SNAME("MenuHover"), EditorStringName(EditorStyles)));
	distraction_free->set_icon(theme->get_icon(SNAME("DistractionFree"), EditorStringName(EditorIcons)));
	bottom_panel_raise->set_icon(theme->get_icon(SNAME("ExpandBottomDock"), EditorStringName(EditorIcons)));
	if (gui_base->is_layout_rtl()) {
		dock_tab_move_left->set_icon(theme->get_icon(SNAME("Forward"), EditorStringName(EditorIcons)));
		dock_tab_move_right->set_icon(theme->get_icon(SNAME("Back"), EditorStringName(EditorIcons)));
	} else {
		dock_tab_move_left->set_icon(theme->get_icon(SNAME("Back"), EditorStringName(EditorIcons)));
		dock_tab_move_right->set_icon(theme->get_icon(SNAME("Forward"), EditorStringName(EditorIcons)));