### 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
ERR_FAIL_COND_V_MSG(p_class.is_empty(), nullptr, "Class name cannot be empty.");
	EditorData &ed = EditorNode::get_editor_data();
	
	if (p_script.is_valid()) {
		Ref<Texture2D> script_icon = ed.get_script_icon(p_script);
		if (script_icon.is_valid()) {
			return script_icon;
		}
		if (p_fallback_script_to_theme) {
			
			
			String script_class_name = p_script->get_language()->get_global_class_name(p_script->get_path());
			String base_type = ScriptServer::get_global_class_native_base(script_class_name);
			if (theme.is_valid() && theme->has_icon(base_type, EditorStringName(EditorIcons))) {
				return theme->get_icon(base_type, EditorStringName(EditorIcons));
			}
		}
	}
	
	
	
	Ref<Texture2D> ext_icon = ed.extension_class_get_icon(p_class);
	if (ext_icon.is_valid()) {