Q1131 How can I hide the password entered via a prompt dialogue?

<script language="JavaScript"><!--
function getPassword() {
    WinId = window.open('','newwin','width=100,height=100');
    if (!WinId.opener) WinId.opener = self;
    Text = '<form ';
    Text += 'onSubmit="opener.location=this.password.value + \'.html\'; self.close()">';
    Text += '<input type="password" name="password">';
    Text += '<\/form>';
    WinId.document.open();
    WinId.document.write(Text);
    WinId.document.close();
}
//--></script>