I installed tmux in iTerm 2.(Build 3.0.13) When I execute vim in tmux, syntax highlighting looks like this.But outside tmux, syntax highlighting looks fine.My $TERM inside and outside tmux is xterm-256color. I also added set -g default-terminal screen-256colorin .tmux.conf and added thisset t_Co=256set t_AB=mset t_AF=mif &term =~ '256color'    set t_ut=endifin .vimrc.I also tried tmux -2 command and read these questions.lose vim colorscheme in tmux modeIncorrect colors with vim in iTerm2 using SolarizedIs this a problem of tmux, vim, or my configuration?EDIT:My .vimrc in GitHub Gisthttps://gist.github.com/sohnryang/3c63397f332f2e30c7d7b2a83c3c9f52
No syntax highlighting in tmux
syntax highlighting;tmux
Well, I solved the problem by myself.as @Carpetsmoker commented, I started to suspect that my .vimrc is a problem. I read this question and started vim with this command inside tmux.vim -u NONE -U NONE -N ~/.vimrcAfter starting vim with command above, I ran this command inside vim.:syn on:colorscheme solarized8_darkThese highlighted my .vimrc file. So, I started to debug my .vimrc.Long story short, set termguicolors was the problem. If I ran vim with set termguicolors commented in .vimrc, I could see corrected syntax highlighting in tmux.