Mozilla Thunderbird makes e-mailing safer, faster, and easier with such features as intelligent spam filters, a built-in RSS reader, and quick search. Thunderbird was designed to prevent viruses and to stop junk mail. Thunderbird 3 includes tabbed e-mail, new search tools and indexing, smart folders, support for Firefox's Personas, a simplified setup wizard, and robust junk protections that include phishing and spam filters.
What's new in this version:
Drag & Drop a contact name from Thunderbird address book (list view) to address box in a new message "compose" window failed.
UI elements became larger when moused over on retina displays/monitor on Mac OS X
Automatic correspondents column upgrade disabled
DIGEST-MD5 authentication in JS-XMPP failed for some users (now disabled).
Font indicator in compose falsely claimed certain fonts were not installed.
Printing failed in composition window. ...