Support reveal's lazy loading feature
I use a lot of images and iframes, so this is essential. It ought to be the default (and maybe it is).
We use reveal.js’ lazy-loading with the default viewDistance setting (3) for all Slides presentations. I don’t think it makes sense to expose viewDistance as a setting since it’s not something most people need to think about.
This doesn't seem to be working for iframes. They are only initiating loading when the presentation gets to that slide.
Max Rahder commented
You'd need to let us set the viewDistance preload count too, to avoid getting a load delay on every page.