Review for New Mail Icon by Dean Jones
Rated 4 out of 5 stars
Worked fine for me. If you install from the mozdev site, there is no xpi for version 1.2.4 currently, but you can get it from http://downloads.mozdev.org/moztraybiff/mozTrayBiff-1.2.4-tb2.0.0.16-rev2.xpi
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