Add to do note for laterg

src/python_spectrometer/core.py

@@ -1089,6 +1089,8 @@ class Spectrometer:
         # TODO: Instead of setting up separate LiveView's for time and frequency
         #       data, the cleaner option would arguably be to subclass and add
         #       another subplot.
+        # TODO: When plot_timetrace=True and one view is paused, closing a
+        #       figure causes the thread to not join.
 
         self._assert_ready()