Function: Add CSS class for the current message depending on starred status.

Function: Filter message threads by those starred by the logged-in user.

Function: Save or delete star message meta according to a message’s star status.

Function: Enqueues the dashicons font.

Function: Add the “Add star” and “Remove star” options to the bulk management list.

Function: Output the link or raw URL for starring or unstarring a message.

Function: Return the link or raw URL for starring or unstarring a message.

Function: Return the starred messages slug. Defaults to ‘starred’.