Sorry, Firefox does not break extensions.
Extension developers that have 18 weeks before a release to get their
extensions compatible and don't get their act together break extensions.
Maybe they should get their act together. You need to contact them and
ask why they didn't.
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openSUSE 12.3 (64-bit) KDE 4.10.2
Thunderbird Earlybird 24.0a2 with Lightning 2.6a2