in relation to "While this module cannot account for different connection speeds (such as WiFi vs. 3g)" - this is my biggest concern with moving to responsive images: that most phones are now retina and therefor bandwidth agnostic image serving is going to degrade performance when serving up retina images to users on mobile connections.
Foresight.js is aimed at fixing this. It has a drupal module → , but very low take up, and, as a module, it doesn't relate to the general d8 direction for images. And it appears depreciated - for reasons I'm not sure I understand.
But so far, even if flawed I'd say it's the best thing going to be able to solve the bandwidth awareness problem.
SO, what would not be to like about supporting foresite.js within picture?
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