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@@ -175,6 +175,8 @@ Github repo. Feel free to jump in and give us your 2 cents!</p>
 <h2>FAQ</h2>
 <h4>How do you pronounce &quot;KDL&quot;?</h4>
 <p>Same as &quot;cuddle&quot;.</p>
+<h4>What is the expected file extension?</h4>
+<p>A file containing KDL should end with <code>.kdl</code>.</p>
 <h4>Why yet another document language?</h4>
 <p>Because nothing out there felt quite right. The closest one I found was
 SDLang, but that had some design choices I disagreed with.</p>