没有“标记为已看见”的操作吗？

[MarcP]

抱歉，我甚至不知道有这样的东西。这是您的答案：

Request: allow "Unseen" as default home page

Dismiss if very hard, this is like asking for Dismiss on the latest tab, there is not trivial way of adding cause a large amount of stuff you have there is not really disimissable.