Problem/Motivation
The removal of jQuery UI includes no longer having use of the :tabbable selector.
Currently, the only way to assign focus via an AJAX Command is using the :tabbable selector in InvokeCommand. There needs to be a way to do this that does not depend on jQuery UI (and ideally no jQuery either). When #3113649: Remove drupal.tabbingmanager's jQueryUI dependency is completed this will be possible.
Steps to reproduce
Proposed resolution
Add a new AJAX command the makes it possible to focus an element.