Website: Add link to Keep Markup plugin in FAQ

faq.html

@@ -75,7 +75,7 @@ <h1>Why is asynchronous highlighting disabled by default?</h1>
 	<h1>Why is pre-existing HTML stripped off?</h1>
 
 	<p>Because it would complicate the code a lot, although it’s not a crucial feature for most people. 
-	If it’s very important to you, there are sufficient hooks to allow you to <a href="extending.html#writing-plugins">write a plugin</a> that retains it.</p>
+	If it’s very important to you, you can use the <a href="plugins/keep-markup/">Keep Markup plugin</a>.</p>
 </section>
 
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