tmux-resurrect/docs/save_dir.md

Resurrect save dir

By default the Tmux environment is saved to a file in the ~/.tmux/resurrect directory if it exists or $XDG_DATA_HOME/tmux/resurrect otherwise (which in turn falls back to ~/.local/share/tmux/resurrect if XDG_DATA_HOME is unset). Change this with:

set -g @resurrect-dir '/some/path'

Using environment variables or shell interpolation in this option is not allowed as the string is used literally. So the following won't do what is expected:

set -g @resurrect-dir '/path/$MY_VAR/$(some_executable)'

Only the following variables and special chars are allowed: $HOME, $HOSTNAME, and ~.