I use the kitty terminal emulator for my day to day development, and I learned that it has these custom escape sequences for fancy underlines. I really wanted to get them working in vim, and after some vimrc tweaks, they started showing up. However, whenever I'm in a tmux session, the codes suddenly stop working. I've read a bit into this and it looks like tmux is 'swallowing' the escape codes, and someone suggested surrounding the sequences like so: "\ePtmux;\e<foo>\e\\, but no luck: no underline/undercurl was showing.
This could be something impossible to do, but I have no idea where to start looking if it isn't, so any help would be appreciated!
My .tmux.conf
set -g default-terminal "xterm-kitty"
set -sg escape-time 0
tmuxso that their maintainers can address this properly.\[\e]0;\u@\h: \w\a\], which works outside tmux, but inside I had to use\ePtmux;\[\e\[\e]0;\u@\h: \w\a\]\e\\\\. It took some experimentation to get the right sequence.