Initial code to shift the panels — this is a simplified version but the actual goal here is to have a system that can "apply" changes to the markup, let's say document mutation (to the iframe, via some sort of micro templating) in a way that it is possible to cancel these events — so friendly to mouse interruptions. So we want to have the best of the "auto pilot" mode and yet to work with the intrusive click (or perhaps one day remote events).