Notification On Mac For New Text
Thunderbird > Preferences > GeneralWhen new messages arrive:uncheck: 'Show an alert'click on OK
First of all, you can always mute the audio on your Mac all together — and sometimes that's a good idea. But other times you may want to hear audio from some apps (like iTunes, for example), but you may want to selectively shut off notification noises from others. On the Notifications screen, first click on the App for which you want to Change the Notification Style and set the notification style to Banners, in case you want the notifications to appear on Mac and disappear on their own, without the need to attend to them. OS X's Notification Center puts you in touch with what's happening on your Mac and elsewhere in the world — displaying banners, alerts, badge notifications and lock screen notifications to let you know what's going on. Use Notifications on your Mac Notifications are a great way for your apps to keep you informed and appear in the upper-right corner of your screen. Learn how to customize alerts and use features like Notification Center and Do Not Disturb.
However, I note that you are using MAC OS and I have heard of something similar before. When you go into Thunderbird > Preferences > General
Maybe that section says:Alerts and default sounds can be stopped by the notification field in system installation.
I found this info in a bug:https://bugzilla.mozilla.org/show_bug.cgi?id=981769
This means:Since OS X 10.8, display of notifications - alert banners/dialogs, badges, and notification sounds - are now the responsibility of the operating system, not the application. The simple fix for this bug then, is to disable and remove all notification sound options from Thunderbird, on OS X 10.8 and above, and let Notification Center deal with it. For the majority of users, and according to Apple, that is the correct solution.
Stop Message Notifications On Mac
So Apple have decided this has to be done via the OS notification of sounds and not via Thunderbird.
