I always duplicate my app with a copy of Google Sheets (that I’ll rename), give it a backup name, set it to my own visibility.
And let the actual one untouched, live.
But I’m still scared each time as the “Duplicate app” command is really too close from the “Delete app”. Even if there’s a confirmation dialog. They both begin with “D”, you never know when your browser suddenly “reacts” quicker than usual.
I really think “dangerous and irreversible options” must be isolated, at least with separators, and far from the other options. And not written in small characters like an ordinary edit option.