Undo works, just type control-Z (on windows) or command-Z (on a mac). It will undo only your own edits. We haven't figured out a way to let people undo other

Undo works, just type control-Z (on windows) or command-Z (on a mac). It will undo only your own edits. We haven't figured out a way to let people undo other users' edits. (We can perform the manipulation on the document, we just haven't figured out a sensible UI for it).