I am on PC, not Mac. Every tutorial and video says to hold down the Alt key while “pulling” one of the shape’s corners to bevel that corner individually. It is not working for me - this bevels all the corners. I am working with a triangle and there is no option in the sidebar menu to set the corners to individual.

Does anyone know why holding Alt to bevel a corner individually is not working? None of the corners have been previously beveled.