### 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
List<StringName> tl;
	theme->get_icon_list(EditorStringName(EditorIcons), &tl);
	for (const StringName &E : tl) {
		if (!ClassDB::class_exists(E)) {
			continue;
		}
		icon_type_cache[E] = theme->get_icon(E, EditorStringName(EditorIcons));
	}
}
void EditorNode::_enable_pending_addons() {
	for (uint32_t i = 0; i < pending_addons.size(); i++) {
		set_addon_plugin_enabled(pending_addons[i], true);
	}
	pending_addons.clear();
}
void EditorNode::_file_dialog_register(FileDialog *p_dialog) {
	singleton->file_dialogs.insert(p_dialog);
}
void EditorNode::_file_dialog_unregister(FileDialog *p_dialog) {
	singleton->file_dialogs.erase(p_dialog);
}
void EditorNode::_editor_file_dialog_register(EditorFileDialog *p_dialog) {