These different flavors are all built from the Code - OSS repository, but with different licensing and default configurations. Notably, only the proprietary builds are permitted to use Microsoft's marketplace and use Microsoft proprietary extensions such as the OmniSharp C# Debugger. The latter is enforced by a handshake mechanism, and cannot be circumvented. For more info on the differences between open source and proprietary "Visual Studio Code" branded builds, consult the Code - OSS GitHub wiki.