Comment 54 for bug 221112

I've just tried this latest configuration.
It doesn't change the behavior of the incriminated application but now no modifiers

Space key alone in xev :

KeyRelease event, serial 31, synthetic NO, window 0x2200001,
    root 0x13b, subw 0x0, time 550680493, (85,98), root:(1666,147),
    state 0x10, keycode 65 (keysym 0x20, space), same_screen YES,
    XLookupString gives 1 bytes: (20) " "
    XFilterEvent returns: False

Left control + space :

KeyPress event, serial 31, synthetic NO, window 0x2200001,
    root 0x13b, subw 0x0, time 550711435, (91,86), root:(1672,135),
    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 31, synthetic NO, window 0x2200001,
    root 0x13b, subw 0x0, time 550714067, (91,86), root:(1672,135),
    state 0x14, keycode 65 (keysym 0x0, NoSymbol), same_screen YES,
    XLookupString gives 0 bytes:
    XmbLookupString gives 0 bytes:
    XFilterEvent returns: False

Right control + space :

KeyPress event, serial 31, synthetic NO, window 0x2200001,
    root 0x13b, subw 0x0, time 550783309, (88,289), root:(1669,338),
    state 0x10, keycode 109 (keysym 0xffe4, Control_R), same_screen YES,
    XLookupString gives 0 bytes:
    XmbLookupString gives 0 bytes:
    XFilterEvent returns: False

KeyPress event, serial 31, synthetic NO, window 0x2200001,
    root 0x13b, subw 0x0, time 550784541, (88,289), root:(1669,338),
    state 0x14, keycode 65 (keysym 0x0, NoSymbol), same_screen YES,
    XLookupString gives 0 bytes:
    XmbLookupString gives 0 bytes:
    XFilterEvent returns: False