I've not found this function after a lot of use, so I'm making the assumption that it's not present.
What I'd like to suggest, is the ability to define separate "Screens" in a single integrated UiFlow Program.
This would operate somewhat like an old "HyperCard" stack, where each "screen" has a separate and defined UI that can be set up via the UiFlow editor.
(Navigation between screens during coding could be added just above the "Units" Selector)
To keep code clean, there could be a "screen 0" that contains code that is present across the whole project (e.g. Wifi Connections, MQTT, Global Variables) and sets instructions for an initial screen display or which screen to switch to.
Screens are traversed via blocks that instruct which screen to switch to, which could be tied to events or button presses.
Events/Functions can be triggered by switching into screens (Much like Setup is used per project) or switching away.
This simple change could clean up messy projects that rely on code to move the screen around, enhance projects that are data driven, make UI design simpler and more intuitive and add a world of function and the opportunity for more complexity into this simple software.