Refused to display..... frame-ancestors https://www.facebook.com

There are several things:

Ensure Facebook page is Published
Under Facebook page settings (Messenger Platform), add your domain. MUST be https:// Make sure domain name matches exactly including www (or lack thereof).
Use correct app_id
Use this page_id (from steps 3 and 4)

If chat plugin works for you and no one else, it's probably because you're logged into FB and you're the page admin. Check steps 1 & 2.

There are two things required to avoid this message:

Ensure you have the correct Facebook page ID set in your HTML. This should be the numeric ID, not what you see in the URL. I found my page's numeric ID via https://findmyfbid.com

Example:
```
<div class="fb-customerchat" page_id="6708927376315932">
</div>
```
Whitelist your domain at Your Page > Settings > Messenger Platform. Ensure this matches your domain, uses HTTPS protocol, and include the port too if using a non-standard port. (And then make sure you hit the Save button!)

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