diff --git a/effects/diminactive/diminactive.cpp b/effects/diminactive/diminactive.cpp
--- a/effects/diminactive/diminactive.cpp
+++ b/effects/diminactive/diminactive.cpp
@@ -199,7 +199,11 @@
         return false;
     }
 
-    if (!w->isManaged()) {
+    if (w->isPopupWindow()) {
+        return false;
+    }
+
+    if (w->isX11Client() && !w->isManaged()) {
         return false;
     }