What is intrinsic content size?
The gist
Intrinsic content size is a view's "natural" size that it computes from its own content without looking at its neighbors: a UILabel from its text and font, a UIImageView from the image size, a UIButton from its title, icon and contentInsets, a UISwitch is fixed. Auto Layout turns this value into a pair of optional constraints on width and height (content hugging and compression resistance), so such views need no explicit width/height: positioning them is enough.
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