Thunderbird Biff 2.1.7

Thunderbird Biff is an extension that will provide a visual indicator of new Thunderbird mail availability in both Firefox and Thunderbird. Install this add-on in BOTH Firefox and Thunderbird as there are both client and server portions.
A new icon is added on the right side of the status bar in both applications. Tool tips are provided for both applications and in Firefox you may click the icon to start/show the default mail program (which I hope will be Thunderbird).
If Firefox is started prior to starting Thunderbird, this add-on will show an unplugged cable icon. When Thunderbird is running, you should see either a plain mail icon (indicates no new mail) or a mail icon with a green arrow (indicates new mail is waiting). In case of error, a "X" icon is shown. Details of the error may be seen if the application is started with the -console argument.
By default, the add-on polls to check for new mail every 10 seconds. You can change this by adding an integer preference called "thunderbirdbiff.intervalSeconds" and setting it to the desired interval (I use 20 seconds).

System requirements:
- Firefox 2.0 - 3.0.*

Enhancements:
- Fixed issue with email startup on Mac platforms with the help of Alan Collins of the UK. Mac installs and manipulates Thunderbird ad a "bundle" (typically called Thunderbird.app) rather than a single executable file. This addon will now properly open the bundle. So on Mac, be sure to set the email path option to point at your Thunderbird.app location.