This has been a repeating issue - from upgrade to upgrade the video widget stops working with a standard MJPEG stream.
It has been working (albeit unreliable) with 2.27.17, but stopped working completely on 2.28.7
Any of the trickery that used to make it work on 2.27 does not work anymore on 2.28
Could you please have a look?
The underlying stream is an MJPEG stream which is activated within 100ms of the WiFi client connection. VLC/Browsers are working fine with the stream.