AT&T Corp has begun shipping a co-branded version of the Netscape Communications Corp Navigator browser for Apple Computer Inc Macintosh users of its WorldNet Service. As with AT&T’s Windows version of Netscape Navigator, the AT&T WorldNet Service Mac browser is to be bundled with the service’s software at no extra charge. In addition, says AT&T, the browser has been specially designed with automated configuration and modem identification processes. It is available on floppy disk or CD-ROM, and members will be able to download future versions free from the AT&T WorldNet Service Web site, according to the company.