Hi,
I am a user of vertical tabs in its current form. I am hearing that vertical tabs will have a 'on-hover' behavior similar to Edge where the sidebar will expand on mouse-over.
One change I would like to see, perhaps a toggle as some may prefer the current behavior, relates to the way the browser handles rendering the current page when the sidebar expands/retracts (at least when the vertical tab view is active). Right now, when the sidebar resizes it triggers a redraw on the current page. I would like to be able to replicate the behavior on Edge, where the page remains stable and doesn't redraw.