(cc'ing some people who might be interested in this kind of stuff) nsIDrawingSurface has some unused functions: IsOffscreen - only used inside the gfx part of the photon port (ie. this function could be made part of only the photon drawing surface) http://lxr.mozilla.org/seamonkey/search?string=IsOffscreen%5C%28 IsPixelAddressable: lxr finds no function calls, only declarations/Definitions http://lxr.mozilla.org/seamonkey/search?string=IsPixelAddressable GetPixelFomat has three callers in SVG code (one of them in debug code), so it probably can not be removed (on first sight, they look like they really need to call it)

nsIDrawingSurface no longer exists, and therefore its unused functions are gone too. ;-)