I’ve started having this problem with the back button skipping over the Unread page as well. Again, I started at the main page, visited my Unread page, and looked at some new posts in one of my tracked threads. In the first thread I pressed the back button, nothing happened for a few seconds, and then I found myself on the main page again.
Going back to my Unread page I visited my second unread thread. When I was finished reading I pressed the back button, was scrolled up to the post I had entered the thread at, and then went immediately back to the main page.
