diff --git a/browser/components/extensions/ext-bookmarks.js b/browser/components/extensions/ext-bookmarks.js
index b8b7650fdb7..874def39721 100644
--- a/browser/components/extensions/ext-bookmarks.js
+++ b/browser/components/extensions/ext-bookmarks.js
@@ -6,7 +6,6 @@ var Bookmarks = PlacesUtils.bookmarks;
 Cu.import("resource://gre/modules/ExtensionUtils.jsm");
 var {
   EventManager,
-  ignoreEvent,
   runSafe,
 } = ExtensionUtils;
 
diff --git a/browser/components/extensions/ext-browserAction.js b/browser/components/extensions/ext-browserAction.js
index 782bf6a2352..1a26eb81528 100644
--- a/browser/components/extensions/ext-browserAction.js
+++ b/browser/components/extensions/ext-browserAction.js
@@ -11,7 +11,6 @@ Cu.import("resource://gre/modules/ExtensionUtils.jsm");
 var {
   EventManager,
   DefaultWeakMap,
-  ignoreEvent,
   runSafe,
 } = ExtensionUtils;
 
diff --git a/browser/components/extensions/ext-pageAction.js b/browser/components/extensions/ext-pageAction.js
index 23a84ed811a..4a48f327d21 100644
--- a/browser/components/extensions/ext-pageAction.js
+++ b/browser/components/extensions/ext-pageAction.js
@@ -6,7 +6,6 @@ Cu.import("resource://gre/modules/ExtensionUtils.jsm");
 var {
   EventManager,
   DefaultWeakMap,
-  ignoreEvent,
   runSafe,
 } = ExtensionUtils;
 
diff --git a/browser/components/extensions/ext-tabs.js b/browser/components/extensions/ext-tabs.js
index 1d778e38834..fbdd60f0beb 100644
--- a/browser/components/extensions/ext-tabs.js
+++ b/browser/components/extensions/ext-tabs.js
@@ -230,7 +230,7 @@ extensions.registerAPI((extension, context) => {
         };
       }).api(),
 
-      onReplaced: ignoreEvent(),
+      onReplaced: ignoreEvent(context, "tabs.onReplaced"),
 
       onRemoved: new EventManager(context, "tabs.onRemoved", fire => {
         let tabListener = event => {
diff --git a/browser/components/extensions/ext-windows.js b/browser/components/extensions/ext-windows.js
index 5333a096f0b..ac09074c49d 100644
--- a/browser/components/extensions/ext-windows.js
+++ b/browser/components/extensions/ext-windows.js
@@ -5,7 +5,6 @@ XPCOMUtils.defineLazyServiceGetter(this, "aboutNewTabService",
 Cu.import("resource://gre/modules/ExtensionUtils.jsm");
 var {
   EventManager,
-  ignoreEvent,
   runSafe,
 } = ExtensionUtils;
 
diff --git a/toolkit/components/extensions/ExtensionContent.jsm b/toolkit/components/extensions/ExtensionContent.jsm
index a5e50fc0fee..c4c80de1b48 100644
--- a/toolkit/components/extensions/ExtensionContent.jsm
+++ b/toolkit/components/extensions/ExtensionContent.jsm
@@ -33,7 +33,6 @@ var {
   runSafeSyncWithoutClone,
   MessageBroker,
   Messenger,
-  ignoreEvent,
   injectAPI,
   flushJarCache,
 } = ExtensionUtils;
diff --git a/toolkit/components/extensions/ExtensionUtils.jsm b/toolkit/components/extensions/ExtensionUtils.jsm
index c7b7b90bcc2..f4393302ff1 100644
--- a/toolkit/components/extensions/ExtensionUtils.jsm
+++ b/toolkit/components/extensions/ExtensionUtils.jsm
@@ -245,12 +245,27 @@ SingletonEventManager.prototype = {
 };
 
 // Simple API for event listeners where events never fire.
-function ignoreEvent()
+function ignoreEvent(context, name)
 {
   return {
-    addListener: function(context, callback) {},
-    removeListener: function(context, callback) {},
-    hasListener: function(context, callback) {},
+    addListener: function(callback) {
+      let id = context.extension.id;
+      let frame = Components.stack.caller;
+      let msg = `In add-on ${id}, attempting to use listener "${name}", which is unimplemented.`;
+      let winID = context.contentWindow.QueryInterface(Ci.nsIInterfaceRequestor)
+        .getInterface(Ci.nsIDOMWindowUtils).currentInnerWindowID;
+      let scriptError = Cc["@mozilla.org/scripterror;1"]
+        .createInstance(Ci.nsIScriptError);
+      scriptError.initWithWindowID(msg, frame.filename, null,
+                                   frame.lineNumber, frame.columnNumber,
+                                   Ci.nsIScriptError.warningFlag,
+                                   "content javascript", winID);
+      let consoleService = Cc['@mozilla.org/consoleservice;1']
+        .getService(Ci.nsIConsoleService);
+      consoleService.logMessage(scriptError);
+    },
+    removeListener: function(callback) {},
+    hasListener: function(callback) {},
   };
 }
 
diff --git a/toolkit/components/extensions/ext-alarms.js b/toolkit/components/extensions/ext-alarms.js
index 9d83c9807da..e294ff09256 100644
--- a/toolkit/components/extensions/ext-alarms.js
+++ b/toolkit/components/extensions/ext-alarms.js
@@ -3,7 +3,6 @@ var { classes: Cc, interfaces: Ci, utils: Cu } = Components;
 Cu.import("resource://gre/modules/ExtensionUtils.jsm");
 var {
   EventManager,
-  ignoreEvent,
   runSafe,
 } = ExtensionUtils;
 
diff --git a/toolkit/components/extensions/ext-cookies.js b/toolkit/components/extensions/ext-cookies.js
index de55dd95aca..d79796a5820 100644
--- a/toolkit/components/extensions/ext-cookies.js
+++ b/toolkit/components/extensions/ext-cookies.js
@@ -2,7 +2,6 @@ const { interfaces: Ci, utils: Cu } = Components;
 Cu.import("resource://gre/modules/ExtensionUtils.jsm");
 var {
   EventManager,
-  ignoreEvent,
   runSafe,
 } = ExtensionUtils;
 
diff --git a/toolkit/components/extensions/ext-notifications.js b/toolkit/components/extensions/ext-notifications.js
index 463ece20bd9..bb8c4be9739 100644
--- a/toolkit/components/extensions/ext-notifications.js
+++ b/toolkit/components/extensions/ext-notifications.js
@@ -138,8 +138,8 @@ extensions.registerPrivilegedAPI("notifications", (extension, context) => {
       }).api(),
 
       // FIXME
-      onButtonClicked: ignoreEvent(),
-      onClicked: ignoreEvent(),
+      onButtonClicked: ignoreEvent(context, "notifications.onButtonClicked"),
+      onClicked: ignoreEvent(context, "notifications.onClicked"),
     },
   };
 });
diff --git a/toolkit/components/extensions/ext-runtime.js b/toolkit/components/extensions/ext-runtime.js
index d77c25cf8ee..c19460e3d81 100644
--- a/toolkit/components/extensions/ext-runtime.js
+++ b/toolkit/components/extensions/ext-runtime.js
@@ -37,7 +37,7 @@ extensions.registerAPI((extension, context) => {
         };
       }).api(),
 
-      onInstalled: ignoreEvent(),
+      onInstalled: ignoreEvent(context, "runtime.onInstalled"),
 
       onMessage: context.messenger.onMessage("runtime.onMessage"),
 
diff --git a/toolkit/components/extensions/ext-storage.js b/toolkit/components/extensions/ext-storage.js
index ed91dbd88ff..697876c4f93 100644
--- a/toolkit/components/extensions/ext-storage.js
+++ b/toolkit/components/extensions/ext-storage.js
@@ -6,7 +6,6 @@ XPCOMUtils.defineLazyModuleGetter(this, "ExtensionStorage",
 Cu.import("resource://gre/modules/ExtensionUtils.jsm");
 var {
   EventManager,
-  ignoreEvent,
   runSafe,
 } = ExtensionUtils;
 
diff --git a/toolkit/components/extensions/ext-webNavigation.js b/toolkit/components/extensions/ext-webNavigation.js
index 4f3ce5787ec..a370c6081af 100644
--- a/toolkit/components/extensions/ext-webNavigation.js
+++ b/toolkit/components/extensions/ext-webNavigation.js
@@ -68,7 +68,7 @@ extensions.registerPrivilegedAPI("webNavigation", (extension, context) => {
       onCompleted: new WebNavigationEventManager(context, "onCompleted").api(),
       onErrorOccurred: new WebNavigationEventManager(context, "onErrorOccurred").api(),
       onReferenceFragmentUpdated: new WebNavigationEventManager(context, "onReferenceFragmentUpdated").api(),
-      onCreatedNavigationTarget: ignoreEvent(),
+      onCreatedNavigationTarget: ignoreEvent(context, "webNavigation.onCreatedNavigationTarget"),
     },
   };
 });
diff --git a/toolkit/components/extensions/test/mochitest/test_ext_notifications.html b/toolkit/components/extensions/test/mochitest/test_ext_notifications.html
index 50e5d4ad85f..24c6eb77bd9 100644
--- a/toolkit/components/extensions/test/mochitest/test_ext_notifications.html
+++ b/toolkit/components/extensions/test/mochitest/test_ext_notifications.html
@@ -17,6 +17,9 @@ add_task(function* test_notifications() {
 
     var opts = {title: "Testing Notification", message: "Carry on"};
 
+    // Test an unimplemented listener.
+    browser.notifications.onClicked.addListener(function() {});
+
     browser.notifications.create("5", opts, function(id) {
       browser.test.sendMessage("running", id);
       browser.test.notifyPass("background test passed");