>When you attempt to reply (unnecessarily) a list of "File# N Choose File ..." fills up the space along with list of "forward this message to". At least the former was not there in old days. I would understand having just one "Choose File" but why 10 when you didn't even have 1 to attach. At least the buttons at the bottom (Send, ...) could be above them to prevent excess scrolling.
When having a message form, you may use the right option of that area to collapse it.