Chat window auto-scrolling

I feel that it is a common and useful feature to have the chat window auto-scroll when the user is already scrolled to the bottom. In other words, if the scrollbar is not at the bottom, auto-scroll should not trigger, but when it is placed at the bottom, auto-scroll should activate, even if the user has moved the scrollbar.

This is a problem, because now, the user must manually scroll whenever lines are added to a conversation.