Little-known fact: It is now possible, in Xcode, while paused in the debugger, to introspect the notification center to learn what objects are registered to receive what notifications:
(lldb) po NotificationCenter.default
<NSNotificationCenter:0x6040000d40b0>
Name, Object, Observer, Options
com.apple.accessibility.reduce.motion.status, 0x10b126190, 0x7fc795700140, 1001
com.apple.accessibility.asst.scanner.status, 0x10b126190, 0x7fc795700140, 1001
// ... etc. ...
Very nice, but how do I go from obtaining the memory address 0x7fc795700140
to learning what object that is?
EDIT I'm leaving this question here, but I think the correct answer is the kind of thing shown at LLDB (Swift): Casting Raw Address into Usable Type
See Question&Answers more detail:
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