Read messages in POP3 accounts are reported as new when they obviously aren't new since they have been read. If behaviour to report also read messages was desired I think an option would be necessary to enable it and IMHO it should be off by default. Not reporting read messages is what is already done for IMAP, so nothing strange or unusual here.
I'm seeing this on 1.2.0, though I'm not able to select it from Version list, so selecting unspecified instead.
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