php
<?php
/**
 * Make standard form fields to make read-only
 * To apply, add CSS class 'wpf-disable-field' (no quotes) to field in form builder
 *
 * @link https://wpforms.com/developers/disable-a-form-field-to-prevent-user-input/
 * 
 * For support, please visit: https://www.facebook.com/groups/wpformsvip
 */
 
function wpf_dev_disable_field() {
    ?>
    <script type="text/javascript">
 
    jQuery(function($) {
 
        $( '.wpf-disable-field input, .wpf-disable-field textarea' ).attr({
             readonly: "readonly",
             tabindex: "-1"
        });
         
    });
 
    </script>
    <?php
}
add_action( 'wpforms_wp_footer_end', 'wpf_dev_disable_field', 30 );