diff --git a/README.md b/README.md
index 6324702..3bc21b0 100644
--- a/README.md
+++ b/README.md
@@ -59,6 +59,11 @@ extension emit one of the following signals :
   * onDblClick
   * onRightDblClick
 
+Other signals are available when extension is activated/deactivated :
+
+  * onActivate
+  * onDeactivate
+
 
 Example
 -------
diff --git a/dbus.xml b/dbus.xml
index d189808..6cc828e 100644
--- a/dbus.xml
+++ b/dbus.xml
@@ -1,4 +1,5 @@
 <interface name="com.soutade.GenericMonitor">
+  <!-- Functions -->
   <method name="notify">
     <arg type="s" direction="in" />
   </method>
@@ -8,6 +9,7 @@
   <method name="deleteGroups">
     <arg type="s" direction="in" />
   </method>
+  <!-- Click events -->
   <signal name="onClick">
     <arg type="s" direction="out" />
   </signal>
@@ -20,4 +22,9 @@
   <signal name="onRightDblClick">
     <arg type="s" direction="out" />
   </signal>
+  <!-- Activate/Deactivate signals -->
+  <signal name="onActivate">
+  </signal>
+  <signal name="onDectivate">
+  </signal>
 </interface>
diff --git a/extension.js b/extension.js
index 7a14aeb..ec2464c 100644
--- a/extension.js
+++ b/extension.js
@@ -49,7 +49,7 @@ class MonitorWidget {
 
         // Don't know why, _rightBox seems undefined on shell 3.36 !!
         if (this.box === undefined) {
-            log(`${box} is undefined, falling back to centerBox`);
+            log(`${box} box is undefined, falling back to center one`);
             this.box = Main.panel._centerBox;
         }
 
@@ -79,7 +79,6 @@ class MonitorWidget {
 
     _addToBox(lastWidget) {
         // lastWidget => NULL, insert at the end
-        // Add to box
         if (this.box !== Main.panel._rigthBox || lastWidget) {
             if (this.icon) {
                 this.box.insert_child_above(this.icon, lastWidget);
@@ -177,6 +176,7 @@ class GenericMonitorDBUS {
         this.clutterSettings = clutter.Settings.get_default();
         this._dbusImpl = Gio.DBusExportedObject.wrapJSObject(loadInterfaceXml('dbus.xml'), this);
         this._dbusImpl.export(Gio.DBus.session, '/com/soutade/GenericMonitor');
+        this._dbusImpl.emit_signal('onActivate', null);
     }
 
     _checkParmeters(parameters) {
@@ -399,6 +399,7 @@ class GenericMonitorDBUS {
     }
 
     destructor() {
+        this._dbusImpl.emit_signal('onDeactivate', null);
         for (let groupIndex in this.monitor_groups) {
             let group = this.monitor_groups[groupIndex];
             for (let itemIndex in group)