That's a Flatpak version of Visual Studio Code, which only works on Linux. Unfortunately, it's unmaintained and stuck on version 1.41.1 (December 2019).
Arch Linux users do have access to a fully open source version of Visual Studio Code in the community repository, which includes access to the Visual Studio Marketplace:
Arch Linux users do have access to a fully open source version of Visual Studio Code in the community repository, which includes access to the Visual Studio Marketplace:
https://www.archlinux.org/packages/community/x86_64/code/