I used to be able to force the icon of a URL resource by adding an URL parameter with the desired file extension. 

Lets's say I have a video with the following link:

https://myvideoplattform.com/View.aspx?id=2642~4o~opjYKry4

Adding this link as a URL resource shows the default resource icon. 

By adding something like &f=.mp4 after the URL I was able to force the video icon. 

This does not work anymore for me. 

I don't know when this stopped working but I'd like to get that behaviour back