Here's a fun bug that only manifests on the Mac. Enter some formatted text so that the HTML is interesting. Then change to HTML view then change back to Normal View...
Now, click the Undo button (not Cmd-Z). On my Mac I see the HTML view text in the Normal box. This will be the new look for the page, unless you click Undo again to get back to the Normal view.
This bug shows up on the editor for posting a message to the forum, and many other places, including using the latest (today) download of the demo code.
Enjoy,
Randal