This already got posted on the Discord, but for the people who haven't heard, Steam recently changed some things with their web browser and inventory system, causing
catsacks awarded from the Spin to Win and media players to break entirely.
Update: catsacks should now work fine:
For the catsacks:
Update: media players are also mostly fixed, it seems
Not sure if it's actually implemented or not, but people in the Discord have been saying they work now so I'm assuming it is.
As for the media players: