→Outstanding "Want To Have" Tasks: Add removing xpcom_obsolete dependency from thunderbird.
* <link rel="offline"> implementation
* Implement rendering of Ogg Theora and possibly other video formats. Ideally with an scriptable API to control animation.
* Help Mailnews/Thunderbird finally get rid of its dependency on xpcom_obsolete as per [[Gecko:Obsolete_API]] and https://bugzilla.mozilla.org/show_bug.cgi?id=38122