setVisibility

System

Hello,

Anyone already succeeded in hiding a button (cgi-callout) in a DCT ?
I am trying this but the button is always visible

...
<script>
<![CDATA[
testButton.setVisibility(false);
]]>
</script>
...
<item name="testButton">
<hidden>
<cgi-callout label="Test Button" />
</hidden>
</item>
...