Lazy loading images is live on mobile (the graph is the page weight graph for the Facebook page on mobile):

We should have a way of keep track of the performance of lazy loading, it will be even more important if we switch to show full articles instead of folded.

I've started trying out super simple scripting of WebPageTest the other day, but need to add a click on opening each folded content. But not 100% how/what we should measure.

combineSteps
navigate    https://en.m.wikipedia.org/wiki/Facebook
execAndWait window.setInterval(scrollBy.bind(window, 0, 600), 1000)