diff --git a/atom/browser/api/atom_api_web_contents.cc b/atom/browser/api/atom_api_web_contents.cc
index d4dd40b81470..e87219d3710e 100644
--- a/atom/browser/api/atom_api_web_contents.cc
+++ b/atom/browser/api/atom_api_web_contents.cc
@@ -90,6 +90,22 @@ struct Converter<PrintSettings> {
   }
 };
 
+template<>
+struct Converter<WindowOpenDisposition> {
+  static v8::Local<v8::Value> ToV8(v8::Isolate* isolate,
+                                   WindowOpenDisposition val) {
+    std::string disposition = "other";
+    switch (val) {
+      case CURRENT_TAB: disposition = "default"; break;
+      case NEW_FOREGROUND_TAB: disposition = "foreground-tab"; break;
+      case NEW_BACKGROUND_TAB: disposition = "background-tab"; break;
+      case NEW_POPUP: case NEW_WINDOW: disposition = "new-window"; break;
+      default: break;
+    }
+    return mate::ConvertToV8(isolate, disposition);
+  }
+};
+
 }  // namespace mate
 
 
@@ -187,10 +203,7 @@ bool WebContents::ShouldCreateWebContents(
     const GURL& target_url,
     const std::string& partition_id,
     content::SessionStorageNamespace* session_storage_namespace) {
-  Emit("-new-window",
-       target_url,
-       frame_name,
-       static_cast<int>(NEW_FOREGROUND_TAB));
+  Emit("new-window", target_url, frame_name, NEW_FOREGROUND_TAB);
   return false;
 }
 
@@ -202,7 +215,7 @@ content::WebContents* WebContents::OpenURLFromTab(
     content::WebContents* source,
     const content::OpenURLParams& params) {
   if (params.disposition != CURRENT_TAB) {
-    Emit("-new-window", params.url, "", static_cast<int>(params.disposition));
+    Emit("new-window", params.url, "", params.disposition);
     return nullptr;
   }
 
diff --git a/atom/browser/api/atom_api_window.cc b/atom/browser/api/atom_api_window.cc
index 0ad9a329e6cc..f19a353afa8c 100644
--- a/atom/browser/api/atom_api_window.cc
+++ b/atom/browser/api/atom_api_window.cc
@@ -58,7 +58,7 @@ void Window::WillCreatePopupWindow(const base::string16& frame_name,
                                    const GURL& target_url,
                                    const std::string& partition_id,
                                    WindowOpenDisposition disposition) {
-  Emit("-new-window", target_url, frame_name, static_cast<int>(disposition));
+  Emit("-new-window", target_url, frame_name);
 }
 
 void Window::WillNavigate(bool* prevent_default, const GURL& url) {
diff --git a/atom/browser/api/lib/web-contents.coffee b/atom/browser/api/lib/web-contents.coffee
index 38e6caaaa6e8..64aaf2bd415c 100644
--- a/atom/browser/api/lib/web-contents.coffee
+++ b/atom/browser/api/lib/web-contents.coffee
@@ -30,17 +30,6 @@ wrapWebContents = (webContents) ->
     do (name, method) ->
       webContents[name] = -> method.apply controller, arguments
 
-  # Translate |disposition| to string for 'new-window' event.
-  webContents.on '-new-window', (args..., disposition) ->
-    disposition =
-      switch disposition
-        when 2 then 'default'
-        when 4 then 'foreground-tab'
-        when 5 then 'background-tab'
-        when 6, 7 then 'new-window'
-        else 'other'
-    @emit 'new-window', args..., disposition
-
   # Tell the rpc server that a render view has been deleted and we need to
   # release all objects owned by it.
   webContents.on 'render-view-deleted', (event, processId, routingId) ->
diff --git a/atom/browser/lib/guest-window-manager.coffee b/atom/browser/lib/guest-window-manager.coffee
index 14b0cafe8f53..aef8b0def24d 100644
--- a/atom/browser/lib/guest-window-manager.coffee
+++ b/atom/browser/lib/guest-window-manager.coffee
@@ -41,7 +41,7 @@ createGuest = (embedder, url, frameName, options) ->
 # Routed window.open messages.
 ipc.on 'ATOM_SHELL_GUEST_WINDOW_MANAGER_WINDOW_OPEN', (event, args...) ->
   [url, frameName, options] = args
-  event.sender.emit '-new-window', event, url, frameName, 7
+  event.sender.emit 'new-window', event, url, frameName, 'new-window'
   if event.sender.isGuest() or event.defaultPrevented
     event.returnValue = null
   else