I was just testing a new method in a class of mine,
and up popped a *Macintosh* (not Squeak) window with
title
	Squeak 3.0.out
and contents some sort of trace.
Hitting Cmd-. has frozen this, and now Squeak doesn't seem to
be responding to anything I do.  The mouse is still tracking,
but I think MacOS is doing that.

Oh yes, the Macintosh menu bar has turned strange.
Now it reads
(Apple) File Edit (Apple) File Edit Help ...... (clock) (Icon) Squeak 3.0
and the second (Apple) item brings up "About SIOUX".
Selecting Quit from the second File menu shut Squeak down entirely.

I *think* a runaway recursion (from a divide-and-conquer gone ever so
slightly wrong) was the cause, but I don't understand the symptom.