Yesterday, using beta 39, I selected a couple of paragraphs and added a comment.
The text highlighter with a yellow background and blue underlining.
The comment box was added correctly in the right-hand column.
After updating to beta 40, I decided to delete the comment. At first glance, it worked and the highlighting of the text disappeared. The comment box also vanished.
Unfortunately, the comment box keeps reappearing. Moving the text to another scene document makes the comment box follow along.
A bug, surely?