set stage overflow from trigger code

Cannot figure out how to change the value of overflow from trigger code. I can't even read it.

    alert(sym.getComposition().getStage().css("overflow"));

No code in the trigger after the above line will run. Lines before run.

Using this link as reference, I thought I could do this:

    sym.getComposition().getStage().css("overflow","visible");

I tried using an intermediate variable. No dice. Any ideas?