diff --git a/qml/articles/9.Falkon_windows.md b/qml/articles/9.Falkon_windows.md
index 2e246a5..2cf0061 100644
--- a/qml/articles/9.Falkon_windows.md
+++ b/qml/articles/9.Falkon_windows.md
@@ -54,7 +54,9 @@ Triggered when new window was created with the new window in parameter.
 
 #### removed(Window)
 Triggered when window was removed (closed) with the window as a
-parameter.
+parameter.  
+The `Window.id` property provided by this signal is `-1` and because of
+this I recommend to use `window` itself as a backup identifier.
 
 ## Window properties
 Each window has some properties which can be read, we can also get to