Also where you don't render the tracks pre and post processing and leave them aside to the ProTools project files. I don't know who expects to open a ProTools project with a bunch of unknown plugins after some years have passed...
Back in the 2000s the Australian government provided software that ran on Windows to prepare and submit your personal tax return. I used to archive my tax return by preparing it in a Windows VM, then storing the whole VM image.
Spanish tax filing software was terrible back in the day. The good part is you would just print it to paper or PDF and archive that :D