Every year I prepare my return 3 different ways, simultaneously. I have all 3 files open on my computer at the same time. No split-screen mode needed. I'm starting with my previous year's return (and there are 3 versions of each one. What I suggest you try is to just copy your current return and change the name of the copy, and open both that copy and the original one together. In other words, open the original one, and whilst that is still open, open the copy. I can't imagine this not working, but if not, then you would have to try something else like doing a "save as" in the 1st one and changing the name for the 2nd one.
In other words, YES it is possible to have more than one return open at the same time! I've been doing that for at least13 years now.
