As a result of the issue I have encountered I thought this was a fairly good idea which maybe in the long run is more better then it seems.
As Shotcut matures it is obvious that when working with your key project it is important to keep the project file and all your work safe. I had an unfortunate event where the hole project got corrupted while trying an experimental feature.
So my first thought was to make an auto-duplicate feature when you save. But that is not going to work because you have already done stuff to your project that might have corrupted it since the last time you worked on it.
So I suggest making it auto-duplicate every time you open your project instead. That way nothing can happen to your previous work.
Then of cause we can talk about current work preservation and also corruption while saving.
That could be mitigated by having a auto-backup copy of current work which would also be a backup for saving corruption. The old save every two minutes feature seems too old-school to me and a more modern save after any user input pause duration of a couple of seconds.
/michael