[tinganho]

I just see one problem with this solution. You can't create Retina images out of base64 strings on any web browsers today.

[madeofpalk]

> You can't create Retina images out of base64 strings

Why not? There's no such thing as a 'retina image', they're just a larger resolution. There's nothing stopping you from requesting a @2x set of thumbnails

[simonw]

Are you sure you can't just serve up a 400x400px base64 image and put it in an image element with a height and width of 200?