thanks
That button won’t do anything for you until you split the editor. Try clicking one of the split view buttons in the top-right of the editor header bar, and then click on a few of the step files. The effect should be obvious at that point. 
It’s a way of setting up a “second binder”, if you will.
Got it, thanks! That what I thought it should do but it wasn’t working for me. I must’ve been doing something weird, cause it’s working now.
Appreciate the response!