[ Version ( since = "2.34" ) ]
public MediaCaptureState display_capture_state { get; set; }
Capture state of the display device.
Whenever the user grants a media-request sent by the web page, requesting screencasting capabilities ( `navigator.mediaDevices.getDisplayMedia()`) this property will be set to webkit_media_capture_state_active .
The application can monitor this property and provide a visual indicator allowing to optionally deactivate or mute the capture device by setting this property respectively to webkit_media_capture_state_none or webkit_media_capture_state_muted.
If the capture state of the device is set to webkit_media_capture_state_none the web-page can still re-request the permission to the user. Permission decision caching is left to the application.