Johnny was one of the first developers outside of Netscape to get involved with the Mozilla source released by Netscape in March 1998. He started working on the source code soon after the release, then working for the Finnish software company Citec. (Citec created DocZilla, a Mozilla-based SGML browser.) In 2000 he was hired by Netscape and moved to California. In 2003 he joined the Mozilla Foundation.