Chord Symbol Durations?

[Daniel McGillicuddy]

I am dusting off my Music21 code after updating and can't seem to get chord symbol durations to work like they used to. 

from music21 import *

MyScore = stream.Score()

MySymbol = harmony.ChordSymbol(root="C", kind="min7")
OtherSymbol = harmony.ChordSymbol(root="F", kind="min7")

MySymbol.duration = duration.Duration(type='half')
OtherSymbol.duration =duration.Duration(type='half')

MyMeasure = stream.Measure()
MyMeasure.append(MySymbol)
MyMeasure.append(OtherSymbol)

MyScore.append(MyMeasure)
harmony.realizeChordSymbolDurations(MyScore)
MyScore.show("xml")

this should put two chords in one measure...? Right? But it doesn't seem to honor the durations of the symbols even with realizeChordSymbolDurations turned on.

Using Python 3.11 and Music21 9.1.0 with MuseScore 4 as the xml reader.

See output