Adding tiny "hint" measures
I'm not sure exactly what these are called, but sometimes there will be tiny measures at the bottom of a page right before a page turn so the performer can turn the page at a more optimal time.
Here's an example from a Beethoven duet. At the bottom of page 9 there is a tiny measure so the cellist knows what to play next:
The hint measure allows the performer to turn to page 10 (shown below) at the rest:
This is definitely not an urgent matter, but would be nice to have when making parts.
Comments
This is possible already
See How to create an ossia with another staff