Various patches and improvements

That's a good question - I'm not sure to be honest. The typical cases I've seen is where some PDF producers convert a single (say) 1000px high original image into 1000 1-line images in the PDF. Having 1000 img/image tags on a single web page will completely kill a desktop web browser, let alone a mobile web browser. I guess therefore we should probably count the actual number of images being drawn (i.e. drawImage), rather than the number of different image objects (setMimeData).