When Sorted "newest first" , the comment will display in the following manner. When user try to add a new comment, the comment box will move up right on top of the "latest comment" so you can see the latest comment as you type in new ones.
[Comment 1] (newest/latest comment)
(click to see 100 older comments)
When sorted "Oldest First", the comment will display in the following manner
[comment 1] (oldest comment)
[comment 5](5th oldest comment)
(click here to see 100 newer comments)
Regardless of the comment order, the newer comments should not be collapsed, as it is time-consuming to expand multiple comments until we reach the newest one.