the default versions of the submenus are located in /usr/share/mxflux/menu

[begin] (MX Fluxbox)
   	[submenu] (All Apps)
   		[exec] (Search) {rofi -show drun}
   		[separator]
   		[include] (~/.fluxbox/submenus/full_menu)
        [separator]
        [exec] (Update)  {/usr/bin/mxfb-menu-generator}
        [exec] (Disable) {mx-tweak --other}
   	[end]
    [separator]
    [exec] (Web browser) {sensible-browser}
    [exec] (File manager) {exo-open $HOME} 
    [exec] (Help) {mxfb-help}
    [submenu] (Multimedia)
    	[exec] (Music player) {deadbeef}
    	[exec] (Webcomic) {bl-xkcd}
        [end]
    [submenu] (Other)
    	[submenu] (Recent files) 
			[include] (~/.fluxbox/submenus/recent_files_menu)
			[separator]
			[exec] (Update) {mxfb-recent-files}
		[end]
		[exec] (Screen capture) {mxfb-quickshot}
		[exec] (Weather) {mxfb-simple-weather}
	[end]
    [exec] (Run) {mxfb-rofirun}
    [exec] (MX Fluxbox tools) {custom-toolbox /etc/custom-toolbox/mxfb-settings.list} 
    [exec] (Terminal) {x-terminal-emulator} 
    [separator]
    [submenu] (Appearance)
    	[include] (~/.fluxbox/submenus/appearance)
    [end]
    [submenu] (Settings)
    	[include] (~/.fluxbox/submenus/settings)
    [end]
    [submenu] (Out of sight)
        [include] (~/.fluxbox/submenus/out-of-sight)
    [end]
    [submenu] (Leave)
        [exec] (Refresh) {fluxbox-remote restart; idesktoggle idesk refresh; nitrogen --restore } 
        [exec] (Suspend) {sudo 'pm-suspend'}
        [exec] (Lock) {dm-tool switch-to-greeter}
        [exit] (Logout) 
        [exec] (Reboot) {sudo /sbin/reboot} 
        [exec] (Shutdown) {sudo poweroff}
    [end]
[end]
