Rated 5 out of 5 stars

This is a really nice add-on. It does what I want and does it simply (even though I only use a portion of its feature set). My use is similar to having a telephone that only rings for certain callers. Most of the time, rather than being notified, I want to look for email when I have time -- for instance, those containing receipts, newsletters, jokes, etc. In other cases, I want to be notified when an email has arrived -- for instance, those sent by close friends, server alerts, etc. To solve this, I use Thunderbird's filters to divide incoming email into designated folders, and Mailbox Alert to give me appropriate notifications for each folder -- such as specific sounds for specific senders and no sounds for others. It's extremely convenient.

This review is for a previous version of the add-on (0.13.1).