1. Add the following to ~/.tmux.conf config file (create if not yet exists):

   set-option -g allow-rename off
   

2. (If tmux is already running) source the updated config file to let it take effect

   Within tmux, enter the following into the command line (<ctrl-B> :; doing once suffices for all windows):

   :source-file ~/.tmux.conf
   

   Or, run the following in shell outside tmux:

   tmux source-file ~/.tmux.conf
   

   • Also possible to kill all open tmux sessions using tmux kill-server; use at user’s risk

Reference:

• https://stackoverflow.com/questions/6041178/keep-the-windows-name-fixed-in-tmux
• https://blog.sanctum.geek.nz/reloading-tmux-config/
• https://unix.stackexchange.com/questions/66606/tmux-not-sourcing-my-tmux-conf