Ctrl-S not working until I create and delete an application shortcut

Hello everyone!
I recently finally changed the layout with localectl instead of just in the xfce4-keyboard-settings, along these instructions in the ArchWiki (Keyboard_configuration_in_Xorg#Using_localectl). Presumably since then, Ctrl-S is not working after startup. By not working, I mean that several programs don’t save the opened file if I press it. The other Ctrl-hotkeys (Ctrl-X, Ctrl-C, Ctrl-V, Ctrl-A, Ctrl-F, …) apparently work fine. However, if I create an application shortcut for Ctrl-S in the xfce4-keyboard-settings and delete it again right away, Ctrl-S does work until the next reboot.

To the best of my knowledge, I do not have any custom Ctrl-S hotkeys anywhere.

My /etc/X11/xorg.conf.d/00-keyboard.conf is as follows:

Section "InputClass"
        Identifier "system-keyboard"
        MatchIsKeyboard "on"
        Option "XkbLayout" "de,de"
        Option "XkbModel" "pc105,pc105"
        Option "XkbVariant" "dvorak,nodeadkeys"
        Option "XkbOptions" "grp:shift_caps_toggle,grp_led:scroll"
EndSection

I have set the xfce4-keyboard-setting layout to “use system defaults”, but that doesn’t seem to make a difference anyway.

My keyboard is a Titanwolf Invader 105-key USB keyboard. It does show up as pointer device in the xfce4-mouse-settings as “SONiX USB DEVICE Keyboard”, which I have deactivated. I don’t know if that has always been the case.

If I use xev, I get right after startup with not working Ctrl-S:

KeyPress event, serial 37, synthetic NO, window 0x4000001,
    root 0x6ba, subw 0x0, time 242330, (87,224), root:(958,669),
    state 0x10, keycode 37 (keysym 0xffe3, Control_L), same_screen YES,
    XLookupString gives 0 bytes: 
    XmbLookupString gives 0 bytes: 
    XFilterEvent returns: False

FocusOut event, serial 37, synthetic NO, window 0x4000001,
    mode NotifyGrab, detail NotifyAncestor

FocusIn event, serial 37, synthetic NO, window 0x4000001,
    mode NotifyUngrab, detail NotifyAncestor

KeymapNotify event, serial 37, synthetic NO, window 0x0,
    keys:  32  0   0   0   32  0   0   0   0   0   0   0   0   0   0   0   
           0   0   0   0   0   0   0   0   0   0   0   0   0   0   0   1   

KeyRelease event, serial 37, synthetic NO, window 0x4000001,
    root 0x6ba, subw 0x0, time 242922, (87,224), root:(958,669),
    state 0x14, keycode 37 (keysym 0xffe3, Control_L), same_screen YES,
    XLookupString gives 0 bytes: 
    XFilterEvent returns: False

After creating and deleting a shortcut, I get:

KeyPress event, serial 37, synthetic NO, window 0x4000001,
    root 0x6ba, subw 0x0, time 332065, (14,363), root:(885,808),
    state 0x10, keycode 37 (keysym 0xffe3, Control_L), same_screen YES,
    XLookupString gives 0 bytes: 
    XmbLookupString gives 0 bytes: 
    XFilterEvent returns: False

KeyPress event, serial 37, synthetic NO, window 0x4000001,
    root 0x6ba, subw 0x0, time 332200, (14,363), root:(885,808),
    state 0x14, keycode 47 (keysym 0x73, s), same_screen YES,
    XLookupString gives 1 bytes: (13) ""
    XmbLookupString gives 1 bytes: (13) ""
    XFilterEvent returns: False

KeyRelease event, serial 37, synthetic NO, window 0x4000001,
    root 0x6ba, subw 0x0, time 332281, (14,363), root:(885,808),
    state 0x14, keycode 47 (keysym 0x73, s), same_screen YES,
    XLookupString gives 1 bytes: (13) ""
    XFilterEvent returns: False

KeyRelease event, serial 37, synthetic NO, window 0x4000001,
    root 0x6ba, subw 0x0, time 332553, (14,363), root:(885,808),
    state 0x14, keycode 37 (keysym 0xffe3, Control_L), same_screen YES,
    XLookupString gives 0 bytes: 
    XFilterEvent returns: False

So obviously there is a difference. However, I don’t know how to interpret this and where to go from here. I appreciate any help.

Thanks!

Alright, through trial and error I have found the presumable culprit and by that a workaround.

If there is an application shortcut set to Ctrl-Ö (that is the Z key on a QWERTY keyboard) in the xfce4-keyboard-settings, then Ctrl-S does not respond correctly. Shortcuts on Ctrl-Ä are fine, so it’s not about the unconventional letter, I suppose.

I would also like to add, in retrospect, that this problem concerns both the left and the right Ctrl-key.

So, my problem is now kind of solved (to my satisfaction anyway), but not explained. I will gladly provide further answers if anybody wants to hunt the problem down.