eventloop error on exit with wx and ipykernel 7.1.0 #1477

Using wx as a GUI backend for plotting with matplotlib, I'm seeing eventloop errors on exiting Jupyter (console or lab) that look like

Traceback (most recent call last):
  File "/.../lib/python3.13/site-packages/ipykernel/eventloops.py", line 213, in on_timer
    self.func()
    ~~~~~~~~~^^
  File "/.../lib/python3.13/site-packages/ipykernel/eventloops.py", line 197, in wake
    if shell_stream.flush(limit=1):
       ~~~~~~~~~~~~~~~~~~^^^^^^^^^
  File "/.../lib/python3.13/site-packages/zmq/eventloop/zmqstream.py", line 450, in flush
    self._check_closed()
    ~~~~~~~~~~~~~~~~~~^^
  File "/.../lib/python3.13/site-packages/zmq/eventloop/zmqstream.py", line 651, in _check_closed
    raise OSError("Stream is closed")
OSError: Stream is closed

usually repeating several (perhaps a dozen) times.

I see #1458 fixed several eventloop issues for plotting with matplotlib.

I believe the eventloops.loop_wx function could be improved to avoid these messages, and I will post a candidate PR.

For reference, I am trying to improve the combination of (my own) wxmplot.interactive plotting package (https://newville.github.io/wxmplot/index.html) with ipython/jupyter. This works well, but I would prefer to avoid the errors on exit.

I looked into monkey-patching the eventloops.loop_wx, but I believe the registration system makes this difficult, and it would not be anyone's preferred approach.