Description:
------------
If I encode a URL with first the function base64_encode() and then with rawurlencode() are appended in the URL may 1 or 2 characters "%3D".

If the length of the URL is divisible by 3, the result is okay.
If the division of the URL length by 3 a remainder of 1, to the url "%3D%3D" attached
With a remainder of 2, "%3D" attached.

Test script:
---------------
$dom = "domain";
for ($i=0; $i<10; $dom.='x', $i++){
	$url = "$dom.ldk";
	$url_e = rawurlencode(base64_encode("$url"));
	printf("%20s (len div 3 = %1d); encoded:%32s; decoded:%s\n",
		$url,
		strlen($url)%3,
		$url_e,
		rawurldecode(base64_decode($url_e)));
}

Expected result:
----------------
          domain.ldk (len div 3 = 1); encoded:            ZG9tYWluLmxkaw%3D%3D; decoded:domain.ldk\nÃÜ
         domainx.ldk (len div 3 = 2); encoded:              ZG9tYWlueC5sZGs%3D; decoded:domainx.ldk7
        domainxx.ldk (len div 3 = 0); encoded:                ZG9tYWlueHgubGRr; decoded:domainxx.ldk
       domainxxx.ldk (len div 3 = 1); encoded:        ZG9tYWlueHh4Lmxkaw%3D%3D; decoded:domainxxx.ldk\nÃÜ
      domainxxxx.ldk (len div 3 = 2); encoded:          ZG9tYWlueHh4eC5sZGs%3D; decoded:domainxxxx.ldk7
     domainxxxxx.ldk (len div 3 = 0); encoded:            ZG9tYWlueHh4eHgubGRr; decoded:domainxxxxx.ldk
    domainxxxxxx.ldk (len div 3 = 1); encoded:    ZG9tYWlueHh4eHh4Lmxkaw%3D%3D; decoded:domainxxxxxx.ldk\nÃÜ
   domainxxxxxxx.ldk (len div 3 = 2); encoded:      ZG9tYWlueHh4eHh4eC5sZGs%3D; decoded:domainxxxxxxx.ldk7
  domainxxxxxxxx.ldk (len div 3 = 0); encoded:        ZG9tYWlueHh4eHh4eHgubGRr; decoded:domainxxxxxxxx.ldk
 domainxxxxxxxxx.ldk (len div 3 = 1); encoded:ZG9tYWlueHh4eHh4eHh4Lmxkaw%3D%3D; decoded:domainxxxxxxxxx.ldk\nÃÜ