( PluggableTextMorph on: nil text: nil accept: nil readSelection: nil menu: nil ) extent: 50@100; editString: 'This is some really long text that will hopefully cause the PTM to wrap and a scollbar appear'; hResizing: #shrinkWrap; openInWorld.
Now either extend the text or just wiggle the scrollbar and watch the PluggableTextMorph widen and widen. The hResizing: #shrinkWrap seems to lead to this behaviour.
Ken