Installing tmux-256color for macOS

macOS has ncurses version 5.7 which doesn't ship the terminfo description for tmux. There're two ways that can help you to solve this problem.

The Fast Blazing Solution

Instead of tmux-256color you can use screen-256color, place this command into your ~/.tmux.conf.

set-option -g default-terminal "screen-256color"

The Right Way

Firstly, we need to install latest version of ncurses by using brew.

$ brew install ncurses

After that, we're going to use infocmp that prints a terminfo description.

$ /usr/local/opt/ncurses/bin/infocmp tmux-256color > ~/tmux-256color.info

Finally, we need to compile the description to our system database and set default-terminal into ~/.tmux.conf.

$ sudo tic -xe tmux-256color tmux-256color.info

set-option -g default-terminal "tmux-256color"

RGB Colors

Also, don't forget to enable RGB. For instance, if you use Alacritty terminfo outside of tmux.

set-option -sa terminal-overrides ",alacritty:RGB"