mjhjmtu

How can I fix this issue?
This is the code and output I received. This is tmux 2.3 and debian 8.9.

root@ns540540:/# tmux source ~/.tmux.conf
/root/.tmux.conf:1: unknown command: @plugin
/root/.tmux.conf:2: unknown command: assume-paste-time
/root/.tmux.conf:3: unknown command: base-index
/root/.tmux.conf:4: unknown command: bell-action
/root/.tmux.conf:5: unknown command: bell-on-alert
/root/.tmux.conf:6: unknown command: default-command
/root/.tmux.conf:7: unknown command: default-shell
/root/.tmux.conf:8: unknown command: destroy-unattached
/root/.tmux.conf:9: unknown command: detach-on-destroy
/root/.tmux.conf:10: unknown command: display-panes-active-colour
/root/.tmux.conf:11: unknown command: display-panes-colour
/root/.tmux.conf:12: unknown command: display-panes-time
/root/.tmux.conf:13: unknown command: display-time
/root/.tmux.conf:14: unknown command: history-limit
/root/.tmux.conf:15: unknown command: key-table
/root/.tmux.conf:16: unknown command: lock-after-time
/root/.tmux.conf:17: unknown command: lock-command
/root/.tmux.conf:18: unknown command: message-command-style
/root/.tmux.conf:19: unknown command: message-style
/root/.tmux.conf:20: unknown command: mouse
/root/.tmux.conf:21: unknown command: prefix
/root/.tmux.conf:22: unknown command: prefix2
/root/.tmux.conf:23: unknown command: renumber-windows
/root/.tmux.conf:24: unknown command: repeat-time
/root/.tmux.conf:25: unknown command: set-remain-on-exit
/root/.tmux.conf:26: unknown command: set-titles
/root/.tmux.conf:27: unknown command: set-titles-string
/root/.tmux.conf:28: unknown command: status
/root/.tmux.conf:29: unknown command: status-interval
/root/.tmux.conf:30: unknown command: status-justify
/root/.tmux.conf:31: unknown command: status-keys
/root/.tmux.conf:32: unknown command: status-left
/root/.tmux.conf:33: unknown command: status-left-length
/root/.tmux.conf:34: unknown command: status-left-style
/root/.tmux.conf:35: unknown command: status-position
/root/.tmux.conf:36: unknown command: status-right
/root/.tmux.conf:37: unknown command: status-right-length
/root/.tmux.conf:38: unknown command: status-right-style
/root/.tmux.conf:39: unknown command: status-style
/root/.tmux.conf:40: unknown command: update-environment
/root/.tmux.conf:41: unknown command: visual-activity
/root/.tmux.conf:42: unknown command: visual-bell
/root/.tmux.conf:43: unknown command: visual-silence
/root/.tmux.conf:44: unknown command: word-separators

Thanks,
Max

Per the tmux man page, ~/.tmux.conf is the default location for a personal tmux configuration file, so it will be read and applied automatically when you invoke tmux without needing to specify it in any way. If you do want to explicitly specify the config file, you would use the -f option:

$ tmux -f ~/.tmux.conf

The command given in your tutorial is for reloading ~/.tmux.conf into an already running session. It may be executed as

tmux-session$ tmux source-file ~/.tmux.conf

or by typing the tmux escape command sequence (configurable, but by default CTRL + B :) followed by the command source-file ~/.tmux.conf.

If you want settings applied for all users, you can set them in /etc/tmux.conf. This will be read automatically when any user starts tmux.

If you want settings applied for a particular user, set them in ~/.tmux.conf. This will be read automatically when that user starts tmux, and will be applied on top of (overriding) any global preferences from /etc/tmux.conf.

You should not as an ordinary user be sourcing /root/.tmux.conf. If you want this user to have the same settings as previously configured for root, either make them global settings, or copy the /root/.tmux.conf into ~/.tmux.conf so that the user has her personal copy of the tmux configuration.