Online performance wins making collaborative editing in your browser quicker. Collabora Online has a novel model that allows re-using the core LibreOffice Technology to provide rich collaborative editing. Recently we have been been focusing our development on improving the 'feel' and slickness of document editing as a key part of user experience. We have also been working on improving editing performance with larger numbers of concurrent active editors. Come and hear about the things that we've found and fixed, both in COOL and also in the LibreOffice core to improve interactivity and to make collaborative editing fly.