Thanks for the reply, @sem! The problem I’ve run into with floating groups is the fact that they sit above the page content rather than operate as an extension of the page content itself. The reason I say this is I am wanting to create a “static” sidebar that, when hidden, slides out of sight and “brings” the page’s content with it. Here’s an example using a standard group + the awesome new responsive engine; notice the animated transition of the text on the right rather than an abrupt switch.

I can achieve the slide in/out effect. The problem, though, is I can’t get the “sidebar” content to remain fixed to viewport height while letting page content scroll.