Do you know if the issue is only occurring on one particular topic? I realize it may be difficult to confirm this if there aren’t other active topics on the site that have a similar number of posts.
If possible, can you visit the topic with your browser’s web inspector open to its “console” tab? See if scrolling through the topic causes any errors to be displayed in the console.
The console will look similar to the image below. On most browsers, you can open the web inspector either by hitting the F12 key on your keyboard, or by right clicking with your mouse, then selecting “Inspect” from the menu. After opening the Inspector, select the “Console” tab from the list of tabs that’s at the top of the page.
