Hey,
recently I’ve switched to Windows and trying to adapt WSL (linux subsystem) to make it play together with my habits.
This time the issue was Tmux starting bash when I need ZSH. No matter what shell was set by chsh -s command Tmux was don’t care.
The thing I found on stackoverflow is setting default-shell option of Tmux to /bin/zsh (in my case).
Here is what you need to add to your ~/.tmux.conf: