wp_dropdown_categories with multiple select

wp_dropdown_categories.php

<div class="ci-select">
    <?php
        wp_dropdown_categories( array(
            'taxonomy'          => 'property_location',
            'hierarchical'      => true,
            'show_option_none'  => esc_html_x( '-', 'any property location', 'ci_theme' ),
            'option_none_value' => '',
            'name'              => 's_property_location',
            'id'                => 'property_location',
            'selected'          => isset( $_GET['s_property_location'] ) ? $_GET['s_property_location'] : '', // e.x 86,110,786
            'multiple'          => true
        ) );
    ?>
</div>

wp_dropdown_cats.php

<?php

add_filter( 'wp_dropdown_cats', 'wp_dropdown_cats_multiple', 10, 2 );

function wp_dropdown_cats_multiple( $output, $r ) {

    if( isset( $r['multiple'] ) && $r['multiple'] ) {

         $output = preg_replace( '/^<select/i', '<select multiple', $output );

        $output = str_replace( "name='{$r['name']}'", "name='{$r['name']}[]'", $output );

        foreach ( array_map( 'trim', explode( ",", $r['selected'] ) ) as $value )
            $output = str_replace( "value=\"{$value}\"", "value=\"{$value}\" selected", $output );

    }

    return $output;
}