title: Allowing multiple domains for 1 Facebook App (like Tumblr)
body: <p>I am trying to get my website validated with the Facebook object debugger and I'm running into the following error:</p>
  
  <blockquote>
    <p>Object at URL '<a href="http://www.example.com/latest">http://www.example.com/latest</a>' of type
    'smallteaser:teaser' is invalid because the domain
    'www.example.com' is not allowed for the specified application id
    '597566643589666'.</p>
  </blockquote>
  
  <p>This error makes perfect sense since I haven't allowed the example.com domain specific access to the Facebook app. <em>But do I really have to?</em></p>
  
  <p>What I would like to achieve is similar to how Tumblr works when a custom domain is used.
  Say, for example, the website <a href="http://www.davidslog.com">www.davidslog.com</a>: it has the following meta tags:</p>
  
  <pre><code>&lt;meta property="fb:app_id" content="48119224995" /&gt;
  
     --&gt; This is the Tumblr app ID
  
  
  &lt;meta property="og:url" content="http://www.davidslog.com/?og=1" /&gt;
  
     --&gt; This is a custom domain which points to a Tumblr blog
  
  
  &lt;meta property="og:type" content="tumblr-feed:tumblelog" /&gt;
  
     --&gt; This is a custom Tumblr object type (in namespace tumblr-feed)
  </code></pre>
  
  <p>And if you then compare this with, for instance, the domain <a href="http://theartofnotwriting.tumblr.com/">theartofnotwriting.tumblr.com</a>, which has the following metadata:</p>
  
  <pre><code>&lt;meta property="fb:app_id" content="48119224995"&gt;
  
     --&gt; This is the same Tumblr app ID
  
  &lt;meta property="og:url" content="http://theartofnotwriting.tumblr.com/?og=1"&gt;
  
     --&gt; This is a different domain
  
  &lt;meta property="og:type" content="tumblr-feed:tumblelog"&gt;
  </code></pre>
  
  <p>You can clearly see that the same Tumblr app has multiple URLs and everything validates correctly.</p>
  
  <p>So why is it that this Tumblr page validates correctly and mine doesn't? How can a Facebook app be configured to allow being used on multiple domains?</p>