[Minor]: Nodes temporarily flash to expanded / un-nested version when the nested node is hit

[NeedsMoar]

Not a big deal, but when nodes are nested, when execution first hits the nested nodes, all the internal nodes appear for a brief moment causing a visual mess (I'm not using a ton so it's not that horrible) for maybe 1/10s. It doesn't persist or seem to harm anything between generations which is why I said it's minor, but it might be worth looking into if you get bored. :-) Thanks for the extension, I like it for cleaning up small node groups.