The macOS web browser created by Alexander Clauss is iCab.
iCab began in 1999 as a Mac browser derived from Crystal Atari Browser, or CAB, a browser for Atari TOS-compatible computers. Clauss developed it for both Classic Mac OS and later macOS, giving users an alternative during an era when Apple’s browser ecosystem was still changing. Its early versions were notable for navigation conveniences, although they initially lacked support for standards such as CSS and the Document Object Model.
The browser’s history spans several technology shifts. iCab 3 improved rendering with CSS2 and Unicode support, while iCab 4 was rewritten around Apple’s Cocoa API and the WebKit rendering engine. Later releases continued the project for newer macOS versions, and iCab 6 was rebuilt using technologies introduced with macOS Big Sur.
A common mix-up is to treat iCab as a Classic Mac-only relic. Classic Mac support ended after version 3.0.5, but the iCab line continued on modern macOS and also became available for iOS.