There is a "Filter" option for each sub-category (e.g. the "Test" or the "Chit-Chat" area). If I choose in the Filter settings to hide ("close") such an area, it gets executed and hidden immediately with an according info – but it doesn't work continuously. Instead the area is visible again the next time I enter ist parent category and its posts are still listed in the "Unread Posts" and increase the counter there.
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