This conversation bubble (three blue dots inside a white bubble) indicates a thread that has unread posts.
This conversation bubble (solid white) indicates a thread that has been read.
This bubble(solid white) with the solid white circle at the top, indicates a thread you have commented in that has no new posts.
If three blue dots are showing in the bubble, that means there are new posts!
The following icon (solid blue with three white dots) appears on the main page of the forum, where the categories are listed. If it appears like this(three white dots), it means there are unread threads in that category. If it appears solid blue, you have already viewed all threads in that section.
These icons will help you browse the forum more quickly by showing you at a glance where you can find new posts!