Add toolbars to ACF

acf_toolbars_functions.php

<?php

if (! function_exists('st_acf_toolbars'))  {

    function st_acf_toolbars() {
    // Full
    $toolbars['Full'] = array();
    $toolbars['Full'][1] = apply_filters('mce_buttons', array('code','bold', 'italic', 'strikethrough', 'bullist', 'numlist', 'blockquote', 'justifyleft', 'justifycenter', 'justifyright', 'link', 'unlink', 'wp_more', 'spellchecker', 'fullscreen', 'wp_adv' ), $editor_id);
    $toolbars['Full'][2] = apply_filters('mce_buttons_2', array( 'formatselect', 'underline', 'justifyfull', 'forecolor', 'pastetext', 'pasteword', 'removeformat', 'charmap', 'outdent', 'indent', 'undo', 'redo'), $editor_id);
    $toolbars['Full'][3] = apply_filters('mce_buttons_3', array(), $editor_id);
    $toolbars['Full'][4] = apply_filters('mce_buttons_4', array(), $editor_id);

    // Basic
    $toolbars['Basic'] = array();
    $toolbars['Basic'][1] = apply_filters( 'teeny_mce_buttons', array('bold', 'italic', 'underline', 'blockquote', 'strikethrough', 'bullist', 'numlist', 'justifyleft', 'justifycenter', 'justifyright', 'undo', 'redo', 'link', 'unlink', 'fullscreen'), $editor_id );

    // Simple
    $toolbars['Simple'] = array();
    $toolbars['Simple'][1] = apply_filters('teeny_mce_buttons', array( 'code', 'formatselect', 'bold', 'italic', 'bullist', 'numlist', 'justifyleft', 'justifycenter', 'justifyright', 'link', 'unlink', 'removeformat' ), $editor_id);

    return $toolbars;
    }

}
add_filter( 'acf/fields/wysiwyg/toolbars', 'st_acf_toolbars', 1, 1 );

?>