fn.getStyle(): make "propName" argument optional
fn.reloadImg(): use .src getter/setter + handle load errors
Correctly wait for spacer.gif loading
fn.reloadImg(): force remove image from cache
This may fix broken images + reloading from cache looks useless in this case
Update changelog: hiding of setsOpener.xul window
fn.reloadImg(): correctly cast for nsIImageLoadingContent
+ support for old browser versions