Ultimate Member - Display checkbox output in columns

um-custom-checkbox-output.php

<?php

add_filter( "um_view_field_value_checkbox", "my_um_view_field_value_checkbox", 10, 2 );

function my_um_view_field_value_checkbox( $html, $data ) {

    if ( $data['metakey'] != 'your_checkbox_meta_key' ) {
        return $html;
    }

    $html = um_filtered_value( $data['metakey'], $data );
    $html_array = explode( ',', $html );
    $html_array = array_map( 'trim', $html_array );
    $html = '<ul></ul>';

    foreach ( $html_array as $item ) {
        $html .= '<li>' . $item . '</li>';
    }

    $html .= '</ul>'; 

    return $html;
}