Switches to top article when dups

[Baff]

I have a lot of feeds from the same site all in 1 folder, so there are often duplicates of the same article in the folder. I just arrow down the list to mark them as read. Anytime I select an unread dup it switches and selects the top article in that set of dups. This happens whether I select the articles with arrow keys or mouse.

This started happening a couple versions back, .13?