diff --git a/Per-site-switches.md b/Per-site-switches.md
index fcd7b43..3d713ec 100644
--- a/Per-site-switches.md
+++ b/Per-site-switches.md
@@ -4,7 +4,13 @@ Back to [Wiki home](https://github.com/gorhill/uBlock/wiki)
 
 The per-site switches allows you to control uBlock's behavior on a per-site basis.
 
-New in beta 1.16.21: changes to the state of per-site switches will be deemed temporary **if and only if** the [overview panel](https://github.com/gorhill/uBlock/wiki/Quick-guide:-popup-user-interface#the-overview-panel) is visible.
+New in beta 1.16.21: 
+
+Changes to the state of per-site switches will be deemed temporary **if and only if** the [overview panel](https://github.com/gorhill/uBlock/wiki/Quick-guide:-popup-user-interface#the-overview-panel) is visible.
+ 
+When the overview panel is not visible, toggling a per-site switch will cause the change to be permanent (i.e. same behavior as before).
+
+However, when the overview panel is visible, toggling a per-site switch will cause the change to be temporary. In such case, there will be an eraser and a padlock icon in the overview pane, which can be used to revert or persist the current state of all the per-site switches.
 
 ![Popup UI](https://user-images.githubusercontent.com/886325/45713902-7d7f9c80-bb90-11e8-8720-3954b9b98fba.png)