Toggle grid overlay on and off while sharing screen for easier navigation

When someone share their screen and someone else on the call has to help them navigate to a specific place (menu, button, text box) on their screen, it can be sometimes hard, confusing, and consume valuable time. Maybe this option already exists, but as far as I know, it does not.

The presenter should be able to turn on a grid overlay with row and column numbers. Then, the person(s) on the other end can quickly guide the presenter to go to a specific cell (e.g. Row 5, Column 6 or if using Excel notation, cell F5). Once the navigation is completed, the presenter can turn off the grid overlay.