This allows us to clean up DOM elements whose contents may have been blocked by the tracking protection list. In nsIChannelClassifier, we potentially have access through nsIChannel -> nsILoadContext -> nsIDOMWindow.
Yeah, that comment is totally wrong. We don't get an nsILoadContext in asyncOpen. Possibilities: 1) Attach a notification callback to the nsILoadGroup that somehow gets notified when the channel is cancelled. 2) When the callback gets called in the content process (nsDocument?), apply the stylesheet.
Francois, not sure how important that is. If it's outdated, please mark as wontfix, otherwise please apply a priority to it. Thanks!
Not sure what product/component this should go into because it's a Firefox front-end thing, but I guess I'll just keep it in Safe Browsing for now.