This is a fairly persistent issue that appears to be exclusive to Connect, and extremely annoying.

Any time a post accumulates very large numbers of comments (say, 300 or more), Connect will eventually just… stop loading additional comments. At first, scrolling down will load a few more top-level comments, but eventually it’ll just give up and act like there’s no more comments to load, even though there Connect has loaded less than 50 comments out of a 1,000+ comment megathread. Worse yet, if a user direct links to a comment on one of those megathreads, Connect will load a completely empty comment thread. This issue doesn’t occur on Voyager or Jerboa, nor on the web UI.