Requires Gecko 1.8 (Firefox 1.5 / Thunderbird 1.5 / SeaMonkey 1.0) findEntryProperties() Find Properties Used to get properties such as 'type' and 'content-disposition' 'type' is a nsISupportsCString containing the images' mime type such as 'image/png' 'content-disposition' will be a nsISupportsCString containing the header If you call this before any data has been loaded from a URI, it will succe