T164990#3262187 links to a comment that gets hidden behind the yellow "There are a very large number of changes, so older changes are hidden." thing. In the past, the changes got automatically unhidden in that case, that does not seem to be working anymore (Chrome 61, Ubuntu 16.04) - the viewport is positioned at the top of the document, the old comments remain collapsed, and even after manually opening them, the comment is not highlighted in any way (making the link pretty much useless).
This seems to happen when the comment is hidden behind multiple layers of yellow bars (ie. clicking on the yellow bar just once would not load it). It seems like a single load is happening - compare T164990#3262187 and T164990, the second has way more comments hidden.