Enable creation of diagrams not tied to physical page constraints.
I produce diagrams never intended to be printed out - network diagrams, database schema, et al. It is extremely constraining to have to be juggling shapes around to fit in some arbitrary A4 / A3 / whatever sized paper background and always see those edges locking in my work. Let me just have an infinite blank canvas. Or if that exists in Visio, I cannot find it.
thank you T and David for your comment as well! Got scared for a second that it still not possible these days, but all good
David Parker commented
It exists as Page Setup / Page size / Let Visio expand the page as needed