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CloseReview for Exit Button Thunderbird by MilesCh
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Although it's a great feature for Firefox, I don't understand the purpose in TB. If several msgs are open in different windows, hitting the X closes them. And adding the Exit Button does not cause those windows to restore on the next start (is this a bug?)
Also we have the keyboard shortcut Cntrl/Q to File/Exit which is a no-brainer.
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