Sumatra PDF 2.4 (2013-10-01)
Changes in this release:
•full-screen mode for ebooks (Ctrl-L)
•new key bindings:
◦F9 - show/hide menu (not remembered after quitting)
◦F8 - show/hide toolbar
•support WebP images (standalone and in comic books)
•support for RAR5 compressed comic books
•fixed multiple crashes
http://blog.kowalczyk.info/software/sumatrapdf/free-pdf-reader.html