Looking at https://etherscan.io/block/8364113
This block received both an uncle block reward and a block reward but I don't understand why. I thought an uncle block was a block produced at the same time as another block on the main chain and the transactions in it "don't count" as valid transactions (because they're not on the main chain).
So why is it that it gets both rewards (3.75ETH) while a block on the main consensus chain only gets the 2ETH block reward?