_onKeydownGlobal(e) {
        //TODO Find a way to keep the caret position between the alt keyup/keydown states
        if (AutoNumericHelper.character(e) === AutoNumericEnum.keyName.Alt) {
            const hoveredElement = AutoNumericHelper.getHoveredElement();
            if (AutoNumeric.isManagedByAutoNumeric(hoveredElement)) {
                const anElement = AutoNumeric.getAutoNumericElement(hoveredElement);
                if (!anElement.formulaMode && anElement.settings.unformatOnHover) {
                    this.constructor._unformatAltHovered(anElement);
                }
            }
        }
    }
Listen for the `alt` key keydown event globally, and if the event is caught, unformat the AutoNumeric element that is hovered by the mouse.

@param {KeyboardEvent} e
@private