GNU Screen v4.8
lists.gnu.org
lists.gnu.org
(I really hate posting a comment like this, since it seems poor form to point out a competing project on the release notes of some other project. But screen and tmux are so fundamental to dev workflows that if there's an advantage, I was hoping to know about it.)
I know that one can switch to vim-style keybindings in the shell, but they have never felt as "comfortable" (and I use vim as my daily driver).
Last but not least, the default keybinding for splitting in tmux (C-b ") is just awkward. Screen has way better defaults.