Thanks for letting me know. It's an issue with the Ace editor which Squiffy uses, and there's an issue logged on GitHub for it
https://github.com/ajaxorg/ace/issues/2164 - although it doesn't look particularly active.
I've logged this here
https://github.com/textadventures/squif ... r/issues/3 and will investigate replacing the Ace editor with CodeMirror
https://codemirror.net/ - if you could do me a favour, could you see if the demo on the CodeMirror site works better with your screen reader?