@gvgerman,
Nice... there is a long time I was ennoyed by this bug ...
I notice a bug looking like that when opening a thread with a few pages. if you don't open all the pages having an unread post, the marker in the list always mark the thread as having new post. But I don't know if it's the same problem.
A+
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Web:
http://jujuland.pagesperso-orange.fr/
Mail : alain [dot] aupeix [at] wanadoo [dot] fr
Ubuntu 12.04 - Gramps 3.4.9 - Harbour 3.2.0 - Hwgui 2.20-3 - K-Meleon 76.0 rc