Four generic issues for tools-as-plugins illustrated by the distributed editor Saros

Saros is an Eclipse plugin for multi-writer, real-time, distributed collaborative text editing that also includes VoIP, chat, whiteboard, and screen sharing functionality. We present four problematic issues we encountered in the development of Saros: Providing portability, choosing a metaphor, handling clashes in display markups, and attributing incompatibilities correctly to their source. These issues will apply to many other plugins similarly. For three of them, no generic solution approach yet exists but should be worked out.