With macOS Sierra you can use Tabs in more apps than just the Finder and Safari. Most Apple apps such as Pages, TextEdit, Keynote and Numbers support tabs, so you can have several documents open in the same window. Some third-party apps already support tabs. Others will most likely add compatibility in the future.
Will this feature work with MS Excel?
Bruce: not sure. Try it once you have Sierra and let us know.
Bruce Peck - I have looked all through MS Excel and if it allows Tabs, I can't find it anywhere.
Gary, keep up the fine work. It is appreciated.