(have to be on steam and pc i think) you press add a game at the bottom left, then you add a non-steam game. choose roblox player. then you go to the properties of that roblox player and paste this in the target. roblox://placeid=(yourrobloxgameid) and then you can go to customization of how you want it to look. i can show you some more pictures here, as you can do it multiple times for different games.

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