From Mashable:
Gmail turned online email on its ear when it popped up a few years back. Naturally, there are more than just a few Gmail extensions for Firefox for an improved user experience. Want a more dynamic signature? How about the ability to open multiple Gmail accounts at once in the same browser? What about the chance to write your emails from right to left? All of these and more are available via these 13 Gmail extensions.
See the List
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