Mozilla developers beta versions of the four presented the first edition of the Release Candidate e-mail client and newsgroup Firefox 3 Application prepared for Windows, Linux and Mac OS X in a different language editions (including in Polish). A preview of Firefox 3 is intended for testing purposes and should not be used in production environments - read the documentation. It is not clear what changes were introduced compared with the fourth beta release.

Thunderbird 3, which contains more sophisticated filtering and search tools aided by the AutoComplete feature, which uses the resources of, inter alia, address book. New Account wizard is available to the database that describes the most common settings for providers of postal services. Clicked on the e-mails, like the list of folders appear as tabs (tabs). By contrast, activity manager (Activity Manager) minutes of interaction with the Thunderbird mail servers. In the address book, find the box to enter information about the birthdays of people saved contact list.

Search engine in Windows Vista and Mac OS X are henceforth able to search the e-mails received by Thunderbird. In addition, a list of IMAP accounts can be loaded in the background, which improves the working of the program and allows you to work offline.

Extension calendar (Lightning) still does not work with Thunderbird 3 As an alternative, independent application developers recommend Thunderbird.