diff --git a/client/displayservers/X11/atoms.h b/client/displayservers/X11/atoms.h
index 2718fa8d..c1446bf9 100644
--- a/client/displayservers/X11/atoms.h
+++ b/client/displayservers/X11/atoms.h
@@ -34,6 +34,7 @@
   DEF_ATOM(_NET_WM_STATE_FOCUSED, True) \
   DEF_ATOM(_NET_WM_STATE_MAXIMIZED_HORZ, True) \
   DEF_ATOM(_NET_WM_STATE_MAXIMIZED_VERT, True) \
+  DEF_ATOM(_NET_WM_STATE_DEMANDS_ATTENTION, True) \
   DEF_ATOM(_NET_WM_WINDOW_TYPE, True) \
   DEF_ATOM(_NET_WM_WINDOW_TYPE_NORMAL, True) \
   DEF_ATOM(_NET_WM_WINDOW_TYPE_UTILITY, True) \
diff --git a/client/displayservers/X11/x11.c b/client/displayservers/X11/x11.c
index f88d6782..52173a4d 100644
--- a/client/displayservers/X11/x11.c
+++ b/client/displayservers/X11/x11.c
@@ -1827,7 +1827,24 @@ static bool x11IsValidPointerPos(int x, int y)
 
 static void x11RequestActivation(void)
 {
-  // TODO
+  XEvent e =
+  {
+    .xclient = {
+      .type         = ClientMessage,
+      .send_event   = true,
+      .message_type = x11atoms._NET_WM_STATE,
+      .format       = 32,
+      .window       = x11.window,
+      .data.l       = {
+        _NET_WM_STATE_ADD,
+        x11atoms._NET_WM_STATE_DEMANDS_ATTENTION,
+        0
+      }
+    }
+  };
+
+  XSendEvent(x11.display, DefaultRootWindow(x11.display), False,
+      SubstructureNotifyMask | SubstructureRedirectMask, &e);
 }
 
 static void x11InhibitIdle(void)