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Result:

http://www.seeleben.de/extern/link.php?url=http%3A%2F%2Fwww.dedicaces.info%2F
Array
(
    [content-type] => text/html; charset=iso-8859-1
    [transfer-encoding] => chunked
    [connection] => keep-alive
    [keep-alive] => timeout=15
    [date] => Fri, 04 Dec 2020 14:26:13 GMT
    [server] => Apache
    [x-powered-by] => PHP/7.3.25
    [content-encoding] => gzip
)
Array
(
    [url] => http://www.seeleben.de/extern/link.php?url=http%3A%2F%2Fwww.dedicaces.info%2F
    [content_type] => text/html; charset=iso-8859-1
    [http_code] => 404
    [header_size] => 250
    [request_size] => 171
    [filetime] => -1
    [ssl_verify_result] => 0
    [redirect_count] => 0
    [total_time] => 0.109384
    [namelookup_time] => 0.028676
    [connect_time] => 0.037009
    [pretransfer_time] => 0.037084
    [size_upload] => 0
    [size_download] => 1443
    [speed_download] => 13238
    [speed_upload] => 0
    [download_content_length] => -1
    [upload_content_length] => -1
    [starttransfer_time] => 0.108977
    [redirect_time] => 0
    [redirect_url] => 
    [primary_ip] => 217.160.0.50
    [certinfo] => Array
        (
        )

    [primary_port] => 80
    [local_ip] => 78.47.42.177
    [local_port] => 47118
    [http_version] => 2
    [protocol] => 1
    [ssl_verifyresult] => 0
    [scheme] => HTTP
)
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
   "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="de" lang="de">

<head>
<base href="http://www.seeleben.de/extern/" target="_top"></base>
<meta http-equiv="content-type" content="text/html; charset=iso-8859-1" />
<title>Bodensee Ferienwohnungen, Ferienh&auml;user, Pensionen, Gasth&ouml;fe und Hotels - seeleben.de</title>
<meta name="description" content="Private Ferienwohnungen und Ferienhäuser, Pensionen, Hotels und Gasthöfe am Bodensee. Mieten sie die Ferienwohnung direkt beim Vermieter." />
<meta name="keywords" content="Bodensee, Ferienwohnung, Ferienwohnungen, Fewo, Ferienhaus, Ferienhäuser, Bauernhof, Bauernhöfe, Hotel, Hotels, Pension, Pensionen, Apartment, Apartments, Appartment, Appartements, Gasthaus, Gasthäuser, Unterkunft, Unterkünfte" />
<meta name="robots" content="noindex, follow" />
<meta name="revisit-after" content="30 days" />
<meta name="MSSmartTagsPreventParsing" content="TRUE" />
<meta http-equiv="imagetoolbar" content="no" />
<style type="text/css">
* { font-size:100.01%; font-family:'Trebuchet MS', Verdana, Arial, sans-serif; margin:0; padding:0; }
body { font-size:84%; padding:4px; cursor:default; line-height:1.4; color:#000; background:#fff; }
h1,h2,h3 { font-family:'Lucida Grande', Verdana, Arial, sans-serif; font-weight:bold; line-height:1.2; color:#369; }
h1 { font-size:1.1em; padding:4px; border-bottom:1px solid #ccc; }
h2 { font-size:1.0em; padding:4px; }
h3 { font-size:1.0em; padding:4px; }
p { padding:4px; font-size:0.8em; }
span { padding:0.1em; }
a { padding:0.1em; color:#669; text-decoration:underline; cursor:pointer; }
.floatbox { width:100%; overflow:hidden; }
.free { background:#9c9; }
.arrival {
  background-color:#fc9;
  background-image:url('../bilder/icons/belegung-anreise.gif');
  background-repeat:no-repeat;
  background-position:center;
}
.departure {
  background-color:#fc9;
  background-image:url('../bilder/icons/belegung-abreise.gif');
  background-repeat:no-repeat;
  background-position:center;
}
.partly { background:#fc9; }
.occupied, .closed { background:#f66; }
.unknown { background:#ddd; }
table { margin:4px; float:left; border-collapse:separate; border-spacing:1px; border:1px solid #666; }
caption { caption-side:top; font-size:0.9em; text-align:center; }
th, td { vertical-align:top; font-size:0.8em; text-align:center; }
th { padding:0; font-weight:bold; }
td { padding:0.2em; }
</style>
</head>

<body>
  <div id="col2"><div id="col2_content" class="clearfix">

  <!-- bleibt leer bei 2-Spalten-Layout -->

  </div></div>
  <div id="col3"><div id="col3_content" class="clearfix">

    <h1>Fehler</h1>
    <p>Konnte die URL http://www.dedicaces.info/ nicht finden.<br />FEHLER in der Datei /homepages/24/d11855257/htdocs/seeleben/extern/link.php Zeile 39.</p>
    <p>Der Fehler wird f&uuml;r den Administrator protokolliert.</p>

  </div><div id="ie_clearing">&nbsp;</div></div>

</body>

</html>

Fatal error: Uncaught Embed\Exceptions\InvalidUrlException: Invalid url 'http://www.seeleben.de/extern/link.php?url=http%3A%2F%2Fwww.dedicaces.info%2F' (Status code 404) in /var/www/oscarotero.com/www/embed3/src/Embed.php:142 Stack trace: #0 /var/www/oscarotero.com/www/embed3/src/Embed.php(81): Embed\Embed::process() #1 /var/www/oscarotero.com/www/embed3/demo/index.php(216): Embed\Embed::create() #2 {main} thrown in /var/www/oscarotero.com/www/embed3/src/Embed.php on line 142