diff --git a/doc/sandbox.mdwn b/doc/sandbox.mdwn
index 464e8f1a6..685f352b0 100644
--- a/doc/sandbox.mdwn
+++ b/doc/sandbox.mdwn
@@ -71,6 +71,7 @@ Its a WikiWikiWorld!!
 * [Email](mailto:noone@invalid)
 * [![ikiwiki logo](http://ikiwiki.info/logo/ikiwiki.png)](http://ikiwiki.info)
 * <a href="http://www.google.com/">plain old html link</a>
+* [[foo]]
 
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