<?php
/**
 * Register a new teeny mce button for Press This
 *
 * @param array $buttons The teeny mce buttons array.
 * @param int $editor_id The editor id.
 *
 * @return array The filtered teeny mce buttons.
 */
function wpdocs_teeny_mce_button( $buttons, $editor_id ) {
	array_push( $buttons, 'separator', 'my_new_button' );
	return $buttons;
}
add_filter( 'teeny_mce_buttons', 'wpdocs_teeny_mce_button', 10, 2 );