This is one way to do it.
It's not attached to an unload. But, it checks for a "flag" (as JimScott put it) which is a variable,
hidden. If this variable is true then the elements are hidden. If it is false then they are not. The elements in my example are hidden on first load when you get to scene 3 they are revealed and stay revealed until you change the variable back to true. You can do this with another function on another scene load or mouse click. Also the elements that are hidden are done so by giving them a class of hidden. So you can do this with any element that has the class hidden.
hiddenElements.zip (40.4 KB)