After reading your description I did a cursory search of the App Store using "dock" as the search argument and come up with several potential candidates such as Dock Menus, Overflow 3, and Dock Shelf. You might find something there that meets your expectations/needs.

Last edited by joemikeb; 12/22/18 04:13 PM. Reason: Spelling
If we knew what it was we were doing, it wouldn't be called research, would it?

— Albert Einstein