This should make true-color and italics work in your tmux session.
Tested successfully in bash and zsh with latest packages from Arch (with exception of Neovim from Git) 20019-07-07.
- Don't use
&t_8bin your vim config
- Don't set
$TERMin your zshrc, bashrc, etc. Let your terminal set this. So far
xterm-256colorhas worked best for me.