webview does not load on messenger.com

#### Describe the bug
Hi FB team,
I know this is probably not the best place to report a bug like this,
But I have tried different channels of yours, still no answer from any of them.

So, please bear with me here.

I tried your demo chatbot from [https://developers.facebook.com/docs/messenger-platform/getting-started/sample-experience/](https://developers.facebook.com/docs/messenger-platform/getting-started/sample-experience/) on my computer.

But the webview does not load any content from original-coast-clothing website, this situation also applied to all the chatbots on [messenger.com](messenger.com).

I've tested on different browsers (Chrome, Safari, Edge, Firefox), OSs (Windows, MacOS), and disable all the plugins that runs on my browser.

And all my colleagues cannot open it either.

It works fine on IOS and Android App and also on [facebook.com](facebook.com) though.

#### To Reproduce
Steps to reproduce the behavior:
1. Go to [https://www.messenger.com/](https://www.messenger.com/) (web app)
2. Click on any chatbot links that will leads you to a webview window.

#### Expected behavior
Website can be loaded in the iframe.

#### Screenshots

#### Additional context
No.