electron/docs/api/web-security.md

Web Security

Because atom-shell has added node integration to normal web pages, there are some security adjustments that made atom-shell both more safe and more convenient.

Overriding X-Frame-Options header

May websites (including Google and Youtube) use the X-Frame-Options header to disable access to their websites in iframes. In atom-shell you can add a disable-x-frame-options string in the iframe's name to disable this:

<!-- Refused to display -->
<iframe name="google" src="https://google.com"></iframe>
<!-- Loads as expected -->
<iframe name="google-disable-x-frame-options" src="https://google.com"></iframe>

x-frame-options