diff --git a/interface/wx/popupwin.h b/interface/wx/popupwin.h
index fb1030b171..01af6cfa63 100644
--- a/interface/wx/popupwin.h
+++ b/interface/wx/popupwin.h
@@ -84,10 +84,10 @@ public:
     /**
         Popup the window (this will show it too).
 
-        If @a winFocus is non-@NULL, it will be kept focused while this window
-        is shown, otherwise this window itself will receive focus. In any case,
-        the popup will disappear automatically if it loses focus because of a
-        user action.
+        If @a focus is non-@NULL, it will be kept focused while this window
+        is shown if supported by the current platform, otherwise the popup
+        itself will receive focus. In any case, the popup will disappear
+        automatically if it loses focus because of a user action.
 
         @see Dismiss()
     */
diff --git a/src/msw/popupwin.cpp b/src/msw/popupwin.cpp
index eea9c444bc..406733d73d 100644
--- a/src/msw/popupwin.cpp
+++ b/src/msw/popupwin.cpp
@@ -96,7 +96,10 @@ void wxPopupTransientWindow::Popup(wxWindow* focus)
 {
     Show();
 
-    if ( focus )
+    // We can only set focus to one of our children as setting it to another
+    // window would result in an immediate loss of activation and popup
+    // disappearance.
+    if ( focus && IsDescendant(focus) )
         focus->SetFocus();
 }