I am using iframe to open a Jitsi meeting room. This meeting room has video/audio/screen-sharing features. Now my issue is that since it is an iframe, I have to allow permissions for the display media. I do that as you can see given below but I also get these errors:

errorMsg: "Failed to execute 'getDisplayMedia' on 'MediaDevices': Access to the feature \"display-capture\" is disallowed by permission policy."
errorName: "SecurityError"
errorStack: "Error: Failed to execute 'getDisplayMedia' on 'MediaDevices': Access to the feature \"display-capture\" is disallowed by permission policy.\n

Why does this happen and how can I overcome it so that my browser (Chrome/Firefox) can display options for camera, microphone and screen-share?

<iframe id="PDF_iframe" src="https://myHost121.de/downloads/index.html" style="
    position: fixed;
    top: 0;
    bottom: 0;
    left: 0;
    right: 0;
    margin: auto;
    height: 60%;
    width: 60%;
    z-index: 2;
    display: Block;
    allow: camera; microphone; display-capture; autoplay; clipboard-write;
  ">
    </iframe>