In the Layers sidebar, there are jump icons that let you select a child DOM element that's associated with a specific layer. However, once you click on the jump link, there is no way to go backwards and re-select the previous element. On busy/dynamic websites like apple.com, it is very difficult to remember the previous element, and it may have shifted in the DOM Tree Outline due to attribute changes. We should just support back-forward in this tab. As far as I know, the jump links do/should create proper history entries already, so we don't need to do much except make sure that the correct details sidebar is shown when navigating the history entries.
<rdar://problem/29951859>
This is also a big issue for cross references in the accessibility section of Node details sidebar. Generally these are parent-child links, so you can recover, but many children have the same role/label/whatever.