Clash when snow protected page opens itself

[weizman]

<!-- https://wow.com/x.html -->
<script> SNOW(() => {}); </script>
<script> open('https://wow.com/x.html'); </script>

• load https://wow.com/x.html.
• page runs Snow protection.
• page opens new window to https://wow.com/x.html and marks it.
• opened page tries to run snow protection and to mark it, but fails because opener has marked it already.
• infinite loop.

This is tricky, how do i make the opened understand that it is Snow protected without an attacker being able to leverage that?