HTMLImageElement.y
  The read-only HTMLImageElement property
  y indicates the y-coordinate of the
  <img> element's top border edge relative to the root element's
  origin.
  The x and y properties are only valid
  for an image if its display property has the computed value
  table-column or table-column-group. In other words: it has
  either of those values set explicitly on it, or it has inherited it from a containing
  element, or by being located within a column described by either
  <col> or <colgroup>.
Syntax
let imageY = htmlImageElement.y;
Value
  An integer value indicating the distance in pixels from the top edge of the element's
  nearest root element to the top edge of the <img> element's border
  box. The nearest root element is the outermost <html> element that
  contains the image. If the image is in an <iframe>, its
  y is relative to that frame.
  In the diagram below, the top border edge is the top edge of the blue padding area. So
  the value returned by y would be the distance from that point to the top
  edge of the content area.
   
    Note: The y property is only valid if the computed
    value of the image's display property is either
    table-column or table-column-group; in other words,
    either of those are set directly on the <img> or they're
    inherited from a containing element or by being located within a column described
    by either <col> or <colgroup>.
  
Example
See HTMLImageElement.x for example code that demonstrates the use of the HTMLImageElement.y (and HTMLImageElement.x).
Specifications
| Specification | 
|---|
| CSSOM View Module # dom-htmlimageelement-y | 
Browser compatibility
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