Web Security - Prevent Website from opening in an IFrame

For Web Security, prevent website from opening in an IFrame as 'WhatsApp Web' does.

<div>
    <p>WhatsApp Error: Prevention from opening WhatsApp Web in an IFrame.</p>
</div>
<iframe src="https://web.whatsapp.com/" title="My WhatsApp" width=900 height=400></iframe> 

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