That's weird. I went to Internal Storage > public > web_epaper_docs and there were two folders: tmp (empty) and a website domain that I know I'd sent to ereader. But, only that one document from that specific domain was there, and I know I've sent a bunch of stuff to e-reader from my browser. Maybe I had been deleting from the ereader side when I was done with a file without remembering that I'd done so.