Add Link to Widget Title using ACF

acf-widget-title-link.php

<?php // This like is just for code highlighting purpose, don't copy it...

/**
 * Insert link Inside Widget Title
 *
 * Author: Zeshan Ahmed
 * Author URI: https://zeshanahmed.com/
 */
add_filter( 'dynamic_sidebar_params', 'update_dynamic_sidebar_params' );
function update_dynamic_sidebar_params( $params ) {
    // get widget vars
    $widget_name = $params[0]['widget_name'];
    $widget_id = $params[0]['widget_id'];
    
    // bail early if ACF isn't activated. 
    if ( ! function_exists( 'get_field' ) ) {
        return $params;
    }
    
    // add link to widget title.
    $widget_link = get_field( '_widget_title_link', 'widget_' . $widget_id );
    
    if ( $widget_link ) {
        $params[0]['before_title'] = $params[0]['before_title'] . '<a href="' . $widget_link . '">';
        $params[0]['after_title'] = '</a>' . $params[0]['after_title'];
    }

    // return
    return $params;
}