Ribbon Commands

Add-in commands are built on the task pane manifest, use version overrides
Check Office Version - File > Account > Office Updates - 16.0.6326
These commands can be easily manually added to the Quick Access Toolbar

Commands are user interface elements that can be used to extend the office ribbon as well as your add-in start actions.
Using commands you can add buttons to the ribbon and to context menus.

enable and disable buttons in preview
adding contextual tabs
don't currently allow showing and hiding buttons or dynamic changes to labels or icons

Enhancements Suggestions

MaxLength for a resid reference ???

Options - Projects and Solutions - Build and Run - MSBuild project build output verbosity = Diagnostic