This is where distro-specific setup can be performed.
Install the distribution and do not launch the shell when complete.Launches the user's default shell in the user's home directory.(where launcher.exe is replaced by the distro-specific name) This reference launcher provides the following functionality: Developers to create custom Linux distributions that can be sideloaded onto their dev machine.Linux distribution owners to package and submit an application that runs on top of WSL to the Microsoft Store.Once you've built your distro launcher, packaged it along with the required art assets, manifest, and, and digitally signed the package, you will be able to sideload your distro on your own machine(s). Every distro package must include a launcher app, which is responsible for completing installation & registration of your distro with WSL, and for launching new distro instances atop WSL. This is the C++ reference implementation for a Windows Subsystem for Linux (WSL) distribution installer/launcher application.
WSL Distro Launcher Reference Implementation Introduction