--- a/browser/devtools/tilt/TiltVisualizer.jsm
+++ b/browser/devtools/tilt/TiltVisualizer.jsm
@@ -189,17 +189,19 @@ TiltVisualizer.prototype = {
   /**
    * Unregister inspector event listeners.
    */
   unbindInspector: function TV_unbindInspector()
   {
     this._browserTab = null;
 
     if (this.inspector) {
-      this.inspector.selection.off("new-node", this.onNewNodeFromInspector);
+      if (this.inspector.selection) {
+        this.inspector.selection.off("new-node", this.onNewNodeFromInspector);
+      }
       this.inspector = null;
     }
 
     gDevTools.off("inspector-ready", this.onInspectorReady);
     gDevTools.off("toolbox-destroyed", this.onToolboxDestroyed);
 
     Services.obs.removeObserver(this.onNewNodeFromTilt,
                                 this.presenter.NOTIFICATIONS.HIGHLIGHTING);