Ticket #39230: 39230.diff

wp-includes/formatting.php

@@ -3782 +3782 @@
          * link starting with /, # or ? or a php file).
          */
         if ( strpos($url, ':') === false && ! in_array( $url[0], array( '/', '#', '?' ) ) &&
-                ! preg_match('/^[a-z0-9-]+?\.php/i', $url) )
-                $url = 'http://' . $url;
+                ! preg_match('/^[a-z0-9-]+?\.php/i', $url) ) {
+                        $scheme = 'http://';
+                        if ( is_ssl() ) {
+                                $response = wp_remote_get( 'https://' . $url );
+                                if ( ! is_wp_error( $response ) && $response['response']['code'] === 200 ) {
+                                        $scheme = 'https://';
+                                }
+                        }
+                        $url = $scheme . $url;
+                }
 
         // Replace ampersands and single quotes only when displaying.
         if ( 'display' == $_context ) {