I use the Hacker News Enhancement Suite extension for Chrome (by HN user etcet). https://chrome.google.com/webstore/detail/hacker-news-enhancement-s/bappiabcod

I use the Hacker News Enhancement Suite extension for Chrome (by HN user etcet). https://chrome.google.com/webstore/detail/hacker-news-enhancement-s/bappiabcodbpphnojdiaddhnilfnjmpm https://chrome.google.com/webstore/detail/hacker-news-enhanc... When you revisit a comment thread it marks which comments are new since your last visit. You can see an example in the second screenshot in the Chrome Web Store.