diff --git a/options.xhtml b/options.xhtml
index 6ba23ce46..164f7857b 100644
--- a/options.xhtml
+++ b/options.xhtml
@@ -13178,10 +13178,10 @@ boolean</p>
 Left-hand side is the workspace name, and right-hand side is the monitor pattern.</p>
 
 <p><span class="emphasis"><em>Type:</em></span>
-attribute set of (signed integer or string or list of string)</p>
+null or (attribute set of (signed integer or string or list of string))</p>
 
 <p><span class="emphasis"><em>Default:</em></span>
-<code class="literal">{ }</code></p>
+<code class="literal">null</code></p>
 
 <p><span class="emphasis"><em>Example:</em></span></p><pre><code class="programlisting">{
   &quot;1&quot; = 1;