Hello, I wrote https://www.drupal.org/files/issues/2513326_34.patch this monstrosity out of necessity because https://github.com/php/php-src/blob/6e3e1e31e92fd57f12471461fc3496ac057757b0/ext/opcache/ZendAccelerator.c#L149 is_cacheable_stream_path hardwires file:// and phar://
Please give us a chance to override this somehow in PHP 7.1 or even 7.2 since it won't be for a good number of years before we can use it but it would be nice if Drupal 9 didn't need this fun. Thanks much, Karoly Negyesi