According to this question, a banner pops in when a question has been locked or deleted. I'm wondering if we can do the same for answers.
Currently we see the pop-in banner if a user has made a change to their answer. But several times now I've written up long, drawn-out comment to an answer, and in the meantime the user has realized their error and deleted their own answer. Currently I don't know that anything has changed until I hit the "add comment" button. Why isn't there a pop-up to notify me of the delete when it happens, just like the way it works for edits?