See http://bugzilla.mozilla.org/show_bug.cgi?id=100005 for more details. Roland has a fix for this which has been in limbo at mozilla.org due to issues over where code under what licence(s) can go. This should apply at least to all OS/platforms that use X11 as the native graphical environment. Broadway (X as a browser plugin) still has potential, but only if it runs on a browser people still use.
resolved in-tree, seemingly
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