Comment 4 for bug 1786617

Oh and reading the original bug report posted against tmux, this problem is most likely caused because the OP is running tmux in client server mode and the server runs in an environment different from the client (at machine startup). infocmp can find the kitty terminfo because kitty sets the TERMINFO env var to point to its terminfo deifnition file. That env var is likely not present in the environment in which the tmux server is started.

So the fix is to either copy the kitty terminfo files to /usr/share/terminfo or to set TERMINFO in whatever script is used to start the tmux server.