Batch redirect to http instead of https
For debugging try to output the result of:
\Drupal\Core\Url::fromRoute('&lt;front&gt;')-&gt;setAbsolute()-&gt;toString()

Is this the wrong protocol, too? Then your browser terminates with a different protocol than the CDN to your web server.
Symfony is able to detect the correct protocol, but you need to configure the CDN (reverse proxy) in settings.php.