Ok, update made.
The threads that you have already started reading will be fine. Any threads that were "new" just before the update won't be "new" after update (i.e. the green ones will go white). Until new green ones appear, that is.
I should write up how this works in a help page, but in lieu of that...
GREEN topics are new ones that you haven't read yet. As soon as you read them, they become...
LIGHT GREY, which are topics that you have read and where you are up to date, until somebody adds a new reply, which makes them turn...
DARK GREY, indicating that you have read them before, but now they have new posts.
PINK ones are identical to green, except that they indicate urgent/realtime posts.
Some other notes:
- If you haven't read a thread for two days then tracking turns off for that thread.
- Threads that haven't been touched by anyone for more than two days are not tracked at all.
- When old threads are revived, they do not come back as new (green) ones. They appear with no color until you read them.
#3 above is one difference with the old system. Revived threads used to come back to the top and look like new threads.
Please let me know if you see any odd things happening. I might need to tweak the freshness times a bit.
