scale
The scale read-only property of the VisualViewport interface returns the pinch-zoom scaling factor applied to the visual viewport, or 0 if current document is not fully active, or 1 if there is no output device.
The scale read-only property of the VisualViewport interface returns the pinch-zoom scaling factor applied to the visual viewport, or 0 if current document is not fully active, or 1 if there is no output device.