Text Box - Do Not Autofit option different in Flash and HTML5
Something I just noticed which does not behave as I expected -
If you set a text box format to "Do not autofit", but you have more text than can fit in a box, all of the text still appears below the box in the SL application, in preview, and in the Flash output. However in HTML5 output the text will be cut off where the box is actually sized in the SL design.
Since you don't see the different in preview or Flash output, it led to a nasty surprise when I brought up a lesson on and iPad. It seems that this could be considered a bug or at least an unexpected issue.