Mosh parses OSC sequences and handles commands 0, 1, and 2 which set icon and title. However, it seems to discard other OSC sequences, including command 7, which Terminal.app on OS X uses to set the path that the Terminal window represents (which controls the icon used in the titlebar, as well as the behavior when cmd-clicking the titlebar). It would be great if Mosh could transmit this sequence to the client like it does with window title/icon.