Here's a ready-to-copy-and-paste button:
<?xml version="1.0"?>
<button backcol="none" display="both" label_pos="right" textcol="none">
<label>Rename</label>
<icon1>#rename</icon1>
<function type="normal">
<instruction>Rename ADVANCED NOIGNOREEXT</instruction>
</function>
</button>