Improve Data Entry and Accessibility when WordPress ACF after_title field group area is used. Tab order is now natural and overrides the core WP javascript that moves the focus to the_content after #title.

admin.js

// Admin Functions
( function( $ ) {
	// better accessiblity and data entry for ACF
	$(document).ready( function() {
		// if there is a an "after_title" field group
		if ( $( '#acf_after_title-sortables' ).length ) {
			// listen for keydown inside the main title field for any add/edit screen
			$('body.post-new-php, body.post-php').on( 'keydown', '#title', function( e ) {
				var keyCode = event.keyCode || event.which;
				// if the key is tab
				if ( 9 == keyCode ) {
					// don't do the normal core WP behavior
					e.preventDefault();
					// find the first field in the after_title area
					$( '#acf_after_title-sortables .inside > div:first-child' )
						.find( ':input:not([type=hidden])' )
						.focus();
				}
			} );
		}
	} );
} )( jQuery );

/*
Thanks to these Stack Overflow answers for inspiration:
@neiker - https://stackoverflow.com/a/17150138/947370
@gdoron-is-supporting-monica https://stackoverflow.com/a/11278006/947370
@birgire https://wordpress.stackexchange.com/a/127042/41488
*/