I must express myself wrong because it is not possible that you cannot see the problem.
I've just done some test with Chrome and Edge. Under Chrome, the text of the newsfeed scrolls normally a first time, appearing on the right then disappearing on the left. The problem then occurs, when it is supposed to appear again on the right. In fact, only the end of the text is displayed directly in the middle of the newsfeed. There is no more progressive scrolling. Under Edge, the behavior is the same and with my smartphone too.
Take a look on the gif attached on my first message. It displayed perfectly the issue.