Back on topic, I think the issue is related to the way that later versions of browsers (at least on a mac) open up all your old windows whenever you open the program.
So let's say I'm browsing seabreeze, skip to another tab, do some more browsing, then I close Firefox.
Next time I open Firefox it will open the hidden seabreeze window and conveniently hide it for me.
I then open seabreeze active topics in a new window, and the new code on seabreeze shows me all the topics that have been posted since the last time that active topics was opened, which was 5 seconds ago... which is none.
Yes it's annoying for me as well... Bring back the old system!