The red dots are normal if a post is edited by an admin (intended) or if a mod recently deleted a reply you had not yet read (lag while waiting for the site to catch up). Green dots on read posts, though, sounds like a bug unless you've blocked some of the Javascript that the forums require or your browser is caching the page. Try a shift + refresh for the latter to see if that is the cause.
John
Maybe this is an old one without resolution so far but I often see threads or forums with multiple threads showing unread messages available even though none really are. I tend to press the "Mark all as read" button when exiting a forum but will return later and see red dots again for threads which have had no new activity. I'll notice that posts within the thread marked as new are one's I've already seen. I know this will happen after pressing the back button but I don't do this. Is it me or is this a bug?

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