When the XDG_USER_CONFIG variable is not set, tmuxp defaults to using ~/.config/tmuxp. ~/.config is a reasonable guess for XDG_USER_CONFIG (and I'd assume most people who've set XDG_USER_CONFIG have set it to be ~/.config). However, when XDG_USER_CONFIG is set, tmuxp doesn't do os.path.join(os.environ["XDG_USER_CONFIG"], "tmuxp"), instead it simply uses XDG_USER_CONFIG.

Is this difference intentional or just a minor oversight?