Version: (using Devel) Compiler: x86_64-pc-linux-gnu-4.3.2 OS: Linux Installed from: Compiled sources How to Reproduce: enter a keyword in the search line above the "mail browser" hit enter and a reply window will appear also
If the line above the "mail browser" (also known as message list) is the one with "Search" in grey, this is what happens: Yoy type in the search, and the filter is done automatically. Then press enter and you open the current mail (in your case a reply mail) in the mail viewer window.
Ups...what confused me was that with an empty result list and pressing an enter I still got a reply window to a message