I meant the very obvious feature (you might already have it) of objects with properties and a unique id, then a state that indexes snapshots of those objects with different properties. With the ability to diff between states by id of the object. So State1:[Square{id:0, x:0, y:0}], State2:[Square{id:0, x:screen.width, y: screen.width}], where going from state1 to state2 would tween the square from top-left to bottom-right.

I am assuming you already have something like that (you already have the objects, the properties, and some states like undo/redo) and it's about exposing the ui around it with labeled states at the user-level.

> Also, were you in dark mode? It's definitely not intended that the whole screen should change color - a popup should dim the content behind. The whole screen changing color sounds like a bug and I'll investigate.

That's what it was! I tried with light mode in firefox and it worked much better.