When I'm collaborating with others on a single document I'd like to be able to send them messages as I would in a chat client but without switching between windows. I can't see a way to do this from inside a document, is it possible?
There is a built-in chat, which as far as I can tell is only accessible when multiple people have a document open. At the top-right corner, next to the "Comments" and "Share" buttons, there should be a chat icon.
The chat icon appears when another user opens the document. It seems that when all users except you have then closed the document, the icon temporarily remains, but then disappears if the page is reloaded.