1 What did you find unexpected about the prototype?
The need for a full page reload was unexpected.
2 What do you appreciate about the prototype?
The notification bar looks good - not too intrusive - and can be clicked on easily.
3 What do you wish was different about the prototype?
I hoped that it would indicate in some way what the changes actually were, for example with a coloured background. In very long, active discussions, it can be almost impossible to pick out which comments are new – and that's the exactly the scenario in which a warning will most often be triggered. With this prototype, I feel that in long sections I'll still have to find the changes manually by opening up a separate browser tab and looking at the page history while keeping the existing tab open so I don't lose my text
4 What concerns you about the prototype?
The original motivation (Topic:Woomtgg3secx6r2h) was the concern was that changes can result in an embarrassing/socially difficult situation; but this prototype seems cover new comments only, and doesn't address the major concern that the specific post to which I am about to reply has been changed by its editor while I am typing. It's far more important to warn of changes to the comment being replied to than to warn of a new comment added perhaps several screens away from my current position within a long discussion section.
This could easily be addressed by providing two warnings, as appropriate: "The comment you are replying to has been changed" as well as "A new reply has been added".