“random post” link not working after Cloudflare / Cache plugin active

Hey!

I am designing a blog exquisite.style and there is a link on the header menu that displays a random post each time you click on it.

I created a plugin with the following code:

<?php

add_action('init','random_add_rewrite');
function random_add_rewrite() {
       global $wp;
       $wp->add_query_var('random');
       add_rewrite_rule('random/?$', 'index.php?random=1', 'top');
}

add_action('template_redirect','random_template');
function random_template() {
       if (get_query_var('random') == 1) {
               $posts = get_posts('post_type=post&orderby=rand&numberposts=1');
               foreach($posts as $post) {
                       $link = get_permalink($post);
               }
               wp_redirect($link,307);
               exit;
       }
}

The Random Post link on the menu was this one: https://mydomain.com//index.php?random=1

After I activated Cloudflare (with html, css, and js minification), the random post button/link is not working anymore. I also activated a caching plugin.

Does anyone have an idea of how I can fix this and make the random post link work again?

Thank you guys!