The Steam app needs to be updated. You can't tell from the app to download and install a game that has been whitelisted in Proton/SteamPlay.
Hello @KayKay91, this issue is already being tracked at #5964. Closing as a duplicate.
Nothing extracted yet.
The Steam app needs to be updated. You can't tell from the app to download and install a game that has been whitelisted in Proton/SteamPlay.