Trait Change in Pharo 9?

In Pharo 9, the following fails to load:

Metacello new
        baseline: 'Magritte';
        repository: 'github://seandenigris/Magritte';
        load: 'Magritte-Bootstrap'.

Specifically, this method fails to compile:
TMagritteBootstrap >> doesNotUnderstand: aMessage
         
        ^ self magritteDescription
                        detect: [ :d | d accessor handlesSelector: aMessage selector ]
                        ifFound: [ :handler | handler handleMessage: aMessage for: self ]
                        ifNone: [ super doesNotUnderstand: aMessage ].

But instead signals that `send: #doesNotUnderstand: toSuperOf:
TMagritteBootstrap` is “not supported”. There is a comment which is over my
head: “Trait methods are copied to the users and only the last literal is
updated. For directed super send the literal of the super send should be
updated too.”

I feel like this was working previously and would like to understand why
it’s not now and how to fix it.



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Cheers,
Sean
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Sent from: http://forum.world.st/Pharo-Smalltalk-Developers-f1294837.html