Unexpected promote-window when pressing prefix + C-Space

[gotha]

Hi,

when I start tmux and check :list-keys, I see this

bind-key    -T prefix       C-Space              run-shell "/home/<username>/.tmux/plugins/tmux-sessionist/scripts/promote_window.sh '#{session_name}' '#{window_id}' '#{window_name}' '#{pane_current_path}'"

and I don't really know why, the default key binding is C-@ and I haven't set custom one.

My .tmux.conf looks like this

unbind C-b
set -g prefix C-Space
bind C-Space send-prefix
bind Space last-window

bind -n MouseDown3Pane send-keys -M MouseDown3Pane

set -g base-index 1
set -g mouse on
setw -g mode-keys vi

# List of plugins
set -g @plugin 'tmux-plugins/tpm'
set -g @plugin 'tmux-plugins/tmux-sensible'
set -g @plugin 'tmux-plugins/tmux-pain-control'
set -g @plugin 'tmux-plugins/tmux-sessionist'

set -g @plugin 'jimeh/tmux-themepack'
set -g @themepack 'powerline/default/yellow'

set -g @plugin 'christoomey/vim-tmux-navigator'

set -g @plugin 'tmux-plugins/tmux-yank'
set -g @plugin 'tmux-plugins/tmux-copycat'

set -g @plugin 'tmux-plugins/tmux-resurrect'
set -g @resurrect-capture-pane-contents 'on'
set -g @resurrect-strategy-vim 'session'
set -g @resurrect-save-shell-history 'on'

set -g status-right ""

If I add

set g @sessionist-promote-window 'C-123'

this fixes it, and C-@ keeps working but I don't know why.

Does anyone have any idea what could be the issue?

[TheSast]

C-@ and C-Space are equivalent in tmux

[gotha]

thanks