diff --git a/kitty/glfw.c b/kitty/glfw.c
index d104d3071..551fb95a3 100644
--- a/kitty/glfw.c
+++ b/kitty/glfw.c
@@ -435,6 +435,9 @@ static id_type focus_counter = 0;
 static void
 window_focus_callback(GLFWwindow *w, int focused) {
     if (!set_callback_window(w)) return;
+    if (OPT(debug_keyboard)) {
+        fprintf(stderr, "\x1b[35mon_focus_change\x1b[m: window id: 0x%llu focused: %d\n", global_state.callback_os_window->id, focused);
+    }
     // There exist some numbnut Wayland compositors, like kwin, that send mouse
     // press events before focus gained events. So only clear the active drag
     // window if it is not the focused window. See https://github.com/kovidgoyal/kitty/issues/6095