I don't know if this is a bug or what, but I at least noticed that in the demo ( http://eightmedia.github.io/yass.js/demo/ ) the "small" image gets loaded as well as the large one for me..
It's already started loading when the other thing starts downloading a new version.
It would be nice not to incur extra requests for people - maybe the solution is to simply leave the src tag empty? Though that will break non-js websites..
There must be a better solution?
In the docs and demo I also added a solution with a <noscript> fallback image. With this solution, you will need some extra markup (not much), but only have one request.
I have updated the docs with some more info about this, and added a better demo in the repository. https://github.com/EightMedia/yass.js/tree/master/demo