Change determination of absolute path

Determine all strings before ': //' and the result of stream_get_wrappers().

src/Filesystem/Folder.php

@@ -345,7 +345,7 @@ class Folder
      */
     public static function isRegisteredStreamWrapper($path)
     {
-        return preg_match('/^[A-Z]+(?=:\/\/)/i', $path, $matches) &&
+        return preg_match('/^[^:\/\/]+?(?=:\/\/)/i', $path, $matches) &&
             in_array($matches[0], stream_get_wrappers());
     }