I am just now observing https://xquartz.macosforge.org/trac/ticket/1315 for myself for the first time.  I couldn't find a way to add my comment there, so I am opening a new bug.  I have never seen this problem before. To launch the xev program, I had to open the terminal App then type `xev` there.  I moved my mouse over to the xev window, tried clicking in various places, including the close button of the window.  I then moved my mouse back to the Terminal window and used <ctrl-c> to kill xev.  The output of xev during that process was
{{{
: xev
Outer window is 0x1600001, inner window is 0x1600002

PropertyNotify event, serial 8, synthetic NO, window 0x1600001,
    atom 0x27 (WM_NAME), time 4205948376, state PropertyNewValue

PropertyNotify event, serial 9, synthetic NO, window 0x1600001,
    atom 0x22 (WM_COMMAND), time 4205948376, state PropertyNewValue

PropertyNotify event, serial 10, synthetic NO, window 0x1600001,
    atom 0x28 (WM_NORMAL_HINTS), time 4205948376, state PropertyNewValue

CreateNotify event, serial 11, synthetic NO, window 0x1600001,
    parent 0x1600001, window 0x1600002, (10,10), width 50, height 50
border_width 4, override NO

PropertyNotify event, serial 14, synthetic NO, window 0x1600001,
    atom 0x120 (WM_PROTOCOLS), time 4205948376, state PropertyNewValue

MapNotify event, serial 15, synthetic NO, window 0x1600001,
    event 0x1600001, window 0x1600002, override NO

PropertyNotify event, serial 28, synthetic NO, window 0x1600001,
    atom 0xff (_NET_WM_ALLOWED_ACTIONS), time 4205948378, state PropertyNewValue

PropertyNotify event, serial 28, synthetic NO, window 0x1600001,
    atom 0x101 (_NET_WM_STATE), time 4205948378, state PropertyNewValue

ConfigureNotify event, serial 28, synthetic NO, window 0x1600001,
    event 0x1600001, window 0x1600001, (0,0), width 178, height 178,
    border_width 0, above 0x400e26, override NO

ReparentNotify event, serial 29, synthetic NO, window 0x1600001,
    event 0x1600001, window 0x1600001, parent 0x400e2c,
    (0,22), override NO

ConfigureNotify event, serial 29, synthetic NO, window 0x1600001,
    event 0x1600001, window 0x1600001, (0,22), width 178, height 178,
    border_width 0, above 0x0, override NO

PropertyNotify event, serial 30, synthetic NO, window 0x1600001,
    atom 0x101 (_NET_WM_STATE), time 4205948378, state PropertyNewValue

MapNotify event, serial 30, synthetic NO, window 0x1600001,
    event 0x1600001, window 0x1600001, override NO

VisibilityNotify event, serial 30, synthetic NO, window 0x1600001,
    state VisibilityPartiallyObscured

Expose event, serial 30, synthetic NO, window 0x1600001,
    (0,0), width 178, height 10, count 4

Expose event, serial 30, synthetic NO, window 0x1600001,
    (0,10), width 10, height 58, count 3

Expose event, serial 30, synthetic NO, window 0x1600001,
    (68,10), width 110, height 58, count 2

Expose event, serial 30, synthetic NO, window 0x1600001,
    (0,68), width 178, height 95, count 1

Expose event, serial 30, synthetic NO, window 0x1600001,
    (0,163), width 163, height 15, count 0

PropertyNotify event, serial 30, synthetic NO, window 0x1600001,
    atom 0x121 (WM_STATE), time 4205948379, state PropertyNewValue

ConfigureNotify event, serial 30, synthetic YES, window 0x1600001,
    event 0x1600001, window 0x1600001, (0,22), width 178, height 178,
    border_width 2, above 0x400e2c, override NO

FocusIn event, serial 30, synthetic NO, window 0x1600001,
    mode NotifyNormal, detail NotifyNonlinear

KeymapNotify event, serial 30, synthetic NO, window 0x0,
    keys:  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   0   

PropertyNotify event, serial 31, synthetic NO, window 0x1600001,
    atom 0x101 (_NET_WM_STATE), time 4205948379, state PropertyNewValue

PropertyNotify event, serial 31, synthetic NO, window 0x1600001,
    atom 0x101 (_NET_WM_STATE), time 4205948379, state PropertyNewValue

ConfigureNotify event, serial 31, synthetic YES, window 0x1600001,
    event 0x1600001, window 0x1600001, (40,62), width 178, height 178,
    border_width 2, above 0x400e2c, override NO

PropertyNotify event, serial 31, synthetic NO, window 0x1600001,
    atom 0x101 (_NET_WM_STATE), time 4205955130, state PropertyNewValue

FocusOut event, serial 31, synthetic NO, window 0x1600001,
    mode NotifyNormal, detail NotifyNonlinear
}}}

Note that switching between Xquartz windows works, and the windows redraw appropriately, but no windows acknowledge any inputs either by mouse or keyboard.