It looks like this polyfill implements the old spec for srcset, where 'w' descriptors meant viewport max-width. The current spec makes 'w' descriptors mean width of the image, to be used together with the sizes attribute. The functionality for the old 'w' is available by using the picture element.
It looks like this polyfill implements the old spec for srcset, where 'w' descriptors meant viewport max-width. The current spec makes 'w' descriptors mean width of the image, to be used together with the sizes attribute. The functionality for the old 'w' is available by using the picture element.