How to autoinstall Platform extension (e.g. gamescope)?

I am trying to repackage some of my GOG games as flatpaks for convenience and I want to utilize this new GitHub - flathub/org.freedesktop.Platform.VulkanLayer.gamescope extension to have better gaming experience. Is it possible to autoinstall this platform extension if it is not already installed so I can assume that gamescope should be always available?

Do you mean installing gamescope flatpak when the user install your game? I’m not aware that it can be done. I think you need to include it in your manifest file.