Our Download of the Day is Thunderbird 11.0.
New user interface with Tabs above the main menu bar to facilitate navigation and make it more contextual
Various security fixes
Thunderbird notifications may not work properly with Growl 1.3 or later
Fixes a crash seen during importing of Microsoft Outlook profiles
If you are unable to view content for your RSS feeds in the Wide View Layout, you may need to disable the Lightning Calendar add-on if you have it installed or switch to Classic View and restart Thunderbird.
You can read more on, and download Thunderbird 11.0, here.