edit page slide bug

There are 3000 lines of code in the page. I want to comment the last 1500 lines of code. When I added a /* symbol at the 1500th line, I slid the page with the touchpad. As a result, the page suddenly jumped to the beginning of the page, and no matter how I slid, the page did not move. The page can only be slid by sliding the scroll bar, and when the scroll bar slides to the end, the page scrolls to the beginning, just like a loop.