I sometimes make something new from something old, but I’ve had to altered/mangled the original thing beyond repair to make it, and I want the original thing back AND the new thing.
So, I…
1.) Copy the new thing I’ve made. (CTRL-C on PC)
2.) Back-step through the undo history to a point before I’ve mangled it, by using (CTRL-Z on PC).
3.) Paste the new thing (CTRL-V on PC).
You could also (before you start mangling) make a block of your thing. Explode the block and mangle away. Then insert the block to get the original back.