It would be possible but I'm not sure if the impact on speed would be worth it. One would have to go through the same steps as the forum index uses to calculate the new posts.
Perhaps adding an additional field to the user's table that stored the timestamp related to the user's last viewing of the forum index and then counting the number of new posts, based on their groups, since the last time they viewed the forum index?
This would add an additional query to the ubbthreads.php page for storing the timestamp and only require one query on the index page to calculate the number of new posts. Would this suffice?
Is there anyone else that would be interested in such a feature?
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