I read an article on this somewhere and found the link (below) - it is Swedish but Google Translate works fine.
Seemingly it is a TV favourite in Sweden right now, even though nothing much actually happens: the stream consists of a number of webcams that are set up to monitor the migration of moose and the footage (with a 24 hours delay) just plays out as if live, though 'highlights' are show as dots in the timeline that you can jump to.
Dipping in and out of it is oddly addictive, and it seems it is the quietness and slow pace makes it popular with the Swedish audience: it has a screensaver-ish feel about it.
https://www.svtplay.se/video/30781962/den-stora-algvandringen/den-stora-algvandringen-sasong-3-4-maj-08-00-1?id=8rLG4ba