https://developer.mozilla.org/en-US/docs/Web/API/PerformanceElementTiming/naturalHeight
PerformanceElementTiming: naturalHeight property - Web APIs | MDN
The naturalHeight read-only property of the PerformanceElementTiming interface returns the intrinsic height of the image element.
web apispropertymdn
https://www.w3schools.com/JSREF/prop_img_naturalheight.asp
HTML DOM Image naturalHeight Property
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html domimageproperty
https://lists.w3.org/Archives/Public/public-html-bugzilla/2010Apr/0345.html
[Bug 7153] Want standardization of .naturalWidth and .naturalHeight, which some browsers already...