Add Filter for ajax-loader?

This is a suggestion. Any chance you would consider adding a filter so it’s easy to change the HTML output for the ajax-loader (add a PHP filter and localize via wp_localize_script).

I know it can be customized via CSS now which is fantastic, but it would be nice to be able to alter the HTML as well for quicker tweaking such as displaying an font icon without having to override the default CSS.

Thank you for considering!