I had enough messages in my Roundcube inbox that they could not all be displayed on one screen (i.e. the vertical scrollbar was active). I deleted most of the messages by highlighting them all at once and then clicking the Delete icon at the top of the window. The highlighted messages immediately disappeared like they should, leaving only the remaining messages, but then a second (duplicate) set of the remaining messages were added to the window. I "refreshed" the inbox display by switching to another folder and back, and then the remaining messages were displayed correctly.
Dave Ek
