Ubuntu has a unified notification system that posts to your desktop’s upper-right corner (unless you move them), but the Thunderbird email client doesn’t seem to know about them. Make Thunderbird use the same notifications as other apps with this quick terminal fix.
Mozilla has an experimental bit of code that makes Thunderbird use Ubuntu’s libnotify system, but it’s not available as an easily installed extension. The Ubublogger has two commands that turn that code into an XPI file, which you can then install in Thunderbird:
bzr branch lp:~ruben-verweij/libnotify-mozilla/experimental
This will download the files from the experimental branch to your computer. Next, create the addon by browsing to the folder and executing the build.sh script with the following command:
If you’re working with a relatively new or untouched system, you might have to head into the Synaptic package manager (in System->Administration) to install the
bzr packages before you can act on this. And when you’re done, be sure to turn off Thunderbird’s own notification window in your preferences to prevent double-up notifications.
How to install the experimental version of libnotify-mozilla [Ubublogger’s Blog via The Open Sourcerer]