I think Mozilla's Thunderbird is great, but why does it's UI still look so old-fashioned ? I'm talking about the menu on the left with all the folders/icons etc that look like
Online interface for Thunderbird – Get this Extension for Firefox (en-US)
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File:Mozilla Thunderbird 11 Italiano - Win 7.png - Wikimedia Commons
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Thunderbird online Mozilla email client
Thunderbird
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