right click alert Netscape

Hello I have some code that pops an alert on right click when a viewer tries to view source. It works fine in IE how would I get it to work in a Netscape/Mozilla platform?

code:

<script language=”javascript”>
function rclick() {
var mydate=new Date()
var myyear=mydate.getFullYear()
if (event.button==2) {alert(‘Hello World.’)}
}
document.onmousedown=rclick
</SCRIPT>

I am learning and experimenting at this point so any help would be greatly appreciated. Thanks

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