I think the problem is that on Save & View the editor and the realtime connection are destroyed before the ISAVED message is sent to the other users participating in the realtime session. As a result their version is not incremented, leading to a merge conflict on the next autosave (or explicit save). We need to delay the realtime session close until the ISAVED acknowledgment is received. I'm thinking that actionButtons.js should allow listeners of the xwiki:document:saved event to delay leaving the edit mode using a promise.