4th Chapter of Updated Pharo by Example ready for review.
https://ci.inria.fr/pharo-contribution/view/Books/job/UpdatedPharoByExample/lastSuccessfulBuild/artifact/book-result/UnderstandingMessage/UnderstandingMessage.pdf
This one was way simpler than the PharoTour and FirstAplication, so I imagine that the review will be easier too.
Stef Not thinking too much, just doing.
