So, maybe I need to dig into the docs, but this new interface is not working for me. I don't hate it, but it's definitely getting in my way.
Docked Preview refuses to resize in any way that doesn't use the full height of the app's window. Undocking Preview is extremely difficult, especially on a laptop. All the Preview controls are disabled, seemingly all the time. Previewing a Macbook takes up 70% of the app window, leaving maybe 20% for the editor which is now effectively unusable -- coffeescript and line wrapping do not play well together. I also can't reorganize or hide any of the columns to get some workspace back.
I don't say this lightly, because I really love framer, but at the moment, this is a clear step backwards for my productivity.