This is a wrapper script that allows you to easily run Winetricks commands for Steam Play/Proton games among other common Wine features, such as launching external Windows executables. This is often useful when a game requires closed-source runtime libraries or applications that are not included with Proton.
Note: To access Steam libraries on another drives, you need to grant access to them:
flatpak override --user --filesystem=/path/to/other/Steam/Library com.github.Matoking.protontricks