Comment 3 for bug 1330379

I don't really understand what you did, but it seems to work! With tiling and prefetch enabled and prefetch set to 2, scrolling around at a reasonably slow rate pretty much eliminates the rendering placeholders. Great!

It's not clear to me what the prefetch limit represents when tiling is enabled. Is it the number of tiles to prefetch, or the number of pages, for which an approximate number of tiles spanning those pages will be prefetched instead? Though more complicated, the latter would probably be preferred. That way, the prefetch limit always refers to the (approximate) number of pages to prefetch.

Which reminds me, is it possible to add tooltips to some of the settings, to give a more detailed description of what they do?