Clarify.

The built-in forms weren't affected.

whatsnew.htm

@@ -32,7 +32,7 @@ For conditions of distribution and use, see <a href="files/is/license.txt">LICEN
 <p><a name="6.4.1"></a><span class="ver">6.4.1-dev </span><span class="date">(?)</span></p>
 
 <ul>
-  <li>All forms have a taskbar button again even when the wizard hasn't been created yet or is invisible.</li>
+  <li><i>Fix:</i> In 6.4.0, a custom form shown using <tt>[Code]</tt> didn't have a taskbar button if Setup's wizard was not visible at the time.</li>
 </ul>
 
 <p><a name="6.4.0"></a><span class="ver">6.4.0 </span><span class="date">(2025-01-09)</span></p>