Why is ElementaryOS not processing the “V” key when capslock is toggled on?

Question

If I enable capslock on my US keyboard layout Thinkpad X1 Carbon, the "v" key becomes inoperable; nothing happens when I press it until I disable capslock.

Here's the output of xev when capslock is disabled:

KeyPress event, serial 38, synthetic NO, window 0x5a00001,
    root 0x19f, subw 0x0, time 147956195, (90,106), root:(1281,753),
    state 0x0, keycode 55 (keysym 0x76, v), same_screen YES,
    XLookupString gives 1 bytes: (76) "v"
    XmbLookupString gives 1 bytes: (76) "v"
    XFilterEvent returns: False

KeyRelease event, serial 38, synthetic NO, window 0x5a00001,
    root 0x19f, subw 0x0, time 147956282, (90,106), root:(1281,753),
    state 0x0, keycode 55 (keysym 0x76, v), same_screen YES,
    XLookupString gives 1 bytes: (76) "v"
    XFilterEvent returns: False

Normal. With capslock enabled:

FocusOut event, serial 38, synthetic NO, window 0x5a00001,
    mode NotifyGrab, detail NotifyAncestor

FocusOut event, serial 38, synthetic NO, window 0x5a00001,
    mode NotifyUngrab, detail NotifyPointer

FocusIn event, serial 38, synthetic NO, window 0x5a00001,
    mode NotifyUngrab, detail NotifyAncestor

KeymapNotify event, serial 38, synthetic NO, window 0x0,
    keys:  2   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   0   0   0   0   0   

Notably, this happens only in X. If I drop out of X11 to a regular terminal (alt+shift+F2, or similar), "V" is normal with capslock enabled, so it's something weird happening in X11 or Pantheon.

Answer 1

Looks like it's related to a keyboard shortcut associated with this combination. Go to System Settings -> Keyboard.

The tabs Layout and Shortcuts have all configurations for it.

Since I'm using WPS Office I had to install the IBus input method, that has also some configurable shortcuts. Check these out also if that's the case.

If this doesn't work, you can try dconf-editor:

• sudo apt-get install dconf-editor

• dconf-editor

  Make a search for "key" and you'll get a list of key bindings.