Definition and Usage
The <iframe> tag specifies an inline frame.
Example
An inline frame is marked up as follows:
<iframe src="https://www.w3schools.com"></iframe>
An inline frame is used to embed another document within the current HTML document.
Browser Support
Why Signage Manager and vSignage couldn't an inline frame?
1. If you have set 'X-Frame-Options' to 'sameorigin', in your web pages may not display when you publish the web page to a screen
2. If you try to play it directly, you will see iFrame forbidden message.
X-Frame-Options is a security header to prevent a well-known vulnerability called Clickjacking. This instruct browser not to open a web page in a frame or iframe based on the configuration.
You can inject HTTP response header by configuring a web server or network devices. The following guide should help you.
To configure in Apache HTTP, Nginx, F5, WordPress.