The most individual feature of iCab is the iCab-Smiley. Depending on the validity of the HTML of the Website currently viewed, it will smile or look grim. iCab supports JavaScript, CSS and has sophisticated mechanism for filtering JavaScript, cookies and other content. It supports the display of Arabic websites on older Macs, and it is available in a number of languages. iCab was the first Macintosh web browser to support ad filtering. As of January 2004, OmniWeb, Mozilla, Mozilla Firebird, and Safari do to some extent.