Request: Frame selection for scrolling

[mtalexan]

Some webpages have multiple scrolling frames (i.e. GitHub's Diff view when many files were changed). It would be nice to have a keyboard method to change frame selection so other frames can be scrolled as well.

Currently in a case like GitHub's diff view when a long list of files has been changed, the user must click one of the two scrollable frames, and then the scrolling key combination works. There is no way to switch between the frames for focus other than clicking within it. Use the link-select (but not link click) key combination also doesn't shift the focus as it relates to scrolling.