I use emacs --daemon for everything, which means I frequently have several different instances of emacsclient running at a time. I've noticed that if I execute an action which opens a minibuffer, it freezes all of the other clients, as detailed in this question. This is annoying but it's not so bad if I can find the instance of emacsclient which has the open minibuffer and close the buffer.
But if I inadvertently close the terminal running emacsclient, while that client had a minibuffer open, then I can't close the minibuffer, and the end result is that every client is frozen and I have to completely shut down my emacs server, which is an enormous pain, due to having to reopen a ton of files and long-running ansi-term sessions, not to mention potentially losing work.
I don't know of a workaround for this situation. kill -USR2 works for some cases of frozen emacs, but doesn't seem to work for this. I tried kill -HUP but that just ended up nuking the whole server, which is.... not good at all? Help!
C-]from any of the clients unblock the server so that you can continue?C-]seems to have no effect :(