I am curious about the recent appearance of "Go to first new post" in front of the thread titles. I don't understand its purpose.

At first I assumed that in a subsequent session it would take me to the next post ofter the last one read in the thread. It does not. It takes me to the first post in the thread.

There are two other ways to reach the first post in the thread: 1) Click on the thread title and 2) click on the number "1" below the thread title. As it is now this uselessly adds clutter to the thread titles.

I should mention that I am using Firefox as my browser.

Was my original assumption wrong?