diff --git a/components/compositing/constellation.rs b/components/compositing/constellation.rs
index 2daa652f6f4..90d244868ba 100644
--- a/components/compositing/constellation.rs
+++ b/components/compositing/constellation.rs
@@ -30,8 +30,7 @@ use msg::constellation_msg::AnimationState;
 use msg::constellation_msg::WebDriverCommandMsg;
 use msg::constellation_msg::{FrameId, PipelineId};
 use msg::constellation_msg::{Key, KeyModifiers, KeyState, LoadData};
-use msg::constellation_msg::{MozBrowserEvent, NavigationDirection};
-use msg::constellation_msg::{PipelineNamespace, PipelineNamespaceId};
+use msg::constellation_msg::{PipelineNamespace, PipelineNamespaceId, NavigationDirection};
 use msg::constellation_msg::{SubpageId, WindowSizeData};
 use msg::constellation_msg::{self, ConstellationChan, Failure};
 use msg::webdriver_msg;
@@ -44,9 +43,8 @@ use profile_traits::mem;
 use profile_traits::time;
 use sandboxing;
 use script_traits::{CompositorEvent, ConstellationControlMsg, DocumentState, LayoutControlMsg};
-use script_traits::{IFrameLoadInfo, IFrameSandboxState};
+use script_traits::{IFrameLoadInfo, IFrameSandboxState, MozBrowserEvent, TimerEventRequest};
 use script_traits::{LayoutMsg as FromLayoutMsg, ScriptMsg as FromScriptMsg, ScriptThreadFactory};
-use script_traits::{TimerEventRequest};
 use std::borrow::ToOwned;
 use std::collections::HashMap;
 use std::env;
diff --git a/components/compositing/pipeline.rs b/components/compositing/pipeline.rs
index 3c49bbf41db..2a4e3b1999e 100644
--- a/components/compositing/pipeline.rs
+++ b/components/compositing/pipeline.rs
@@ -16,14 +16,14 @@ use ipc_channel::router::ROUTER;
 use layers::geometry::DevicePixel;
 use layout_traits::{LayoutControlChan, LayoutThreadFactory};
 use msg::constellation_msg::{ConstellationChan, Failure, FrameId, PipelineId, SubpageId};
-use msg::constellation_msg::{LoadData, MozBrowserEvent, WindowSizeData};
+use msg::constellation_msg::{LoadData, WindowSizeData};
 use msg::constellation_msg::{PipelineNamespaceId};
 use net_traits::ResourceThread;
 use net_traits::image_cache_thread::ImageCacheThread;
 use net_traits::storage_thread::StorageThread;
 use profile_traits::mem as profile_mem;
 use profile_traits::time;
-use script_traits::{ConstellationControlMsg, InitialScriptState};
+use script_traits::{ConstellationControlMsg, InitialScriptState, MozBrowserEvent};
 use script_traits::{LayoutControlMsg, LayoutMsg, NewLayoutInfo, ScriptMsg};
 use script_traits::{ScriptToCompositorMsg, ScriptThreadFactory, TimerEventRequest};
 use std::mem;
diff --git a/components/msg/constellation_msg.rs b/components/msg/constellation_msg.rs
index d1e9b39b02b..46fda6511e0 100644
--- a/components/msg/constellation_msg.rs
+++ b/components/msg/constellation_msg.rs
@@ -219,61 +219,6 @@ pub enum AnimationState {
     NoAnimationCallbacksPresent,
 }
 
-// https://developer.mozilla.org/en-US/docs/Web/API/Using_the_Browser_API#Events
-#[derive(Deserialize, Serialize)]
-pub enum MozBrowserEvent {
-    /// Sent when the scroll position within a browser `<iframe>` changes.
-    AsyncScroll,
-    /// Sent when window.close() is called within a browser `<iframe>`.
-    Close,
-    /// Sent when a browser `<iframe>` tries to open a context menu. This allows
-    /// handling `<menuitem>` element available within the browser `<iframe>`'s content.
-    ContextMenu,
-    /// Sent when an error occurred while trying to load content within a browser `<iframe>`.
-    Error,
-    /// Sent when the favicon of a browser `<iframe>` changes.
-    IconChange(String, String, String),
-    /// Sent when the browser `<iframe>` has finished loading all its assets.
-    LoadEnd,
-    /// Sent when the browser `<iframe>` starts to load a new page.
-    LoadStart,
-    /// Sent when a browser `<iframe>`'s location changes.
-    LocationChange(String),
-    /// Sent when window.open() is called within a browser `<iframe>`.
-    OpenWindow,
-    /// Sent when the SSL state changes within a browser `<iframe>`.
-    SecurityChange,
-    /// Sent when alert(), confirm(), or prompt() is called within a browser `<iframe>`.
-    ShowModalPrompt(String, String, String, String), // TODO(simartin): Handle unblock()
-    /// Sent when the document.title changes within a browser `<iframe>`.
-    TitleChange(String),
-    /// Sent when an HTTP authentification is requested.
-    UsernameAndPasswordRequired,
-    /// Sent when a link to a search engine is found.
-    OpenSearch,
-}
-
-impl MozBrowserEvent {
-    pub fn name(&self) -> &'static str {
-        match *self {
-            MozBrowserEvent::AsyncScroll => "mozbrowserasyncscroll",
-            MozBrowserEvent::Close => "mozbrowserclose",
-            MozBrowserEvent::ContextMenu => "mozbrowsercontextmenu",
-            MozBrowserEvent::Error => "mozbrowsererror",
-            MozBrowserEvent::IconChange(_, _, _) => "mozbrowsericonchange",
-            MozBrowserEvent::LoadEnd => "mozbrowserloadend",
-            MozBrowserEvent::LoadStart => "mozbrowserloadstart",
-            MozBrowserEvent::LocationChange(_) => "mozbrowserlocationchange",
-            MozBrowserEvent::OpenWindow => "mozbrowseropenwindow",
-            MozBrowserEvent::SecurityChange => "mozbrowsersecuritychange",
-            MozBrowserEvent::ShowModalPrompt(_, _, _, _) => "mozbrowsershowmodalprompt",
-            MozBrowserEvent::TitleChange(_) => "mozbrowsertitlechange",
-            MozBrowserEvent::UsernameAndPasswordRequired => "mozbrowserusernameandpasswordrequired",
-            MozBrowserEvent::OpenSearch => "mozbrowseropensearch"
-        }
-    }
-}
-
 #[derive(Deserialize, Serialize)]
 pub enum WebDriverCommandMsg {
     LoadUrl(PipelineId, LoadData, IpcSender<LoadStatus>),
diff --git a/components/script/dom/document.rs b/components/script/dom/document.rs
index 49afd4dc9ee..65987f4bf3e 100644
--- a/components/script/dom/document.rs
+++ b/components/script/dom/document.rs
@@ -83,13 +83,13 @@ use layout_interface::{LayoutChan, Msg, ReflowQueryType};
 use msg::constellation_msg::{ALT, CONTROL, SHIFT, SUPER};
 use msg::constellation_msg::{AnimationState, PipelineId};
 use msg::constellation_msg::{ConstellationChan, Key, KeyModifiers, KeyState};
-use msg::constellation_msg::{MouseButton, MozBrowserEvent, SubpageId};
+use msg::constellation_msg::{MouseButton, SubpageId};
 use net_traits::ControlMsg::{GetCookiesForUrl, SetCookiesForUrl};
 use net_traits::CookieSource::NonHTTP;
 use net_traits::{AsyncResponseTarget, PendingAsyncLoad};
 use num::ToPrimitive;
 use script_thread::{MainThreadScriptMsg, Runnable};
-use script_traits::MouseEventType;
+use script_traits::{MouseEventType, MozBrowserEvent};
 use script_traits::{ScriptMsg as ConstellationMsg, ScriptToCompositorMsg};
 use script_traits::{TouchEventType, TouchId, UntrustedNodeAddress};
 use std::ascii::AsciiExt;
diff --git a/components/script/dom/htmliframeelement.rs b/components/script/dom/htmliframeelement.rs
index 4d496903629..65cfd32fa17 100644
--- a/components/script/dom/htmliframeelement.rs
+++ b/components/script/dom/htmliframeelement.rs
@@ -26,12 +26,11 @@ use dom::virtualmethods::VirtualMethods;
 use dom::window::Window;
 use js::jsapi::{JSAutoCompartment, JSAutoRequest, RootedValue, JSContext, MutableHandleValue};
 use js::jsval::{UndefinedValue, NullValue};
-use msg::constellation_msg::{ConstellationChan, MozBrowserEvent};
+use msg::constellation_msg::{ConstellationChan};
 use msg::constellation_msg::{NavigationDirection, PipelineId, SubpageId};
 use page::IterablePage;
-use script_traits::IFrameLoadInfo;
 use script_traits::IFrameSandboxState::{IFrameSandboxed, IFrameUnsandboxed};
-use script_traits::ScriptMsg as ConstellationMsg;
+use script_traits::{IFrameLoadInfo, MozBrowserEvent, ScriptMsg as ConstellationMsg};
 use std::ascii::AsciiExt;
 use std::cell::Cell;
 use string_cache::Atom;
diff --git a/components/script/dom/htmllinkelement.rs b/components/script/dom/htmllinkelement.rs
index 58ce5dc6ea0..38bb2287ac3 100644
--- a/components/script/dom/htmllinkelement.rs
+++ b/components/script/dom/htmllinkelement.rs
@@ -24,10 +24,10 @@ use encoding::all::UTF_8;
 use ipc_channel::ipc;
 use ipc_channel::router::ROUTER;
 use layout_interface::{LayoutChan, Msg};
-use msg::constellation_msg::{ConstellationChan, MozBrowserEvent};
+use msg::constellation_msg::ConstellationChan;
 use net_traits::{AsyncResponseListener, AsyncResponseTarget, Metadata};
 use network_listener::{NetworkListener, PreInvoke};
-use script_traits::ScriptMsg as ConstellationMsg;
+use script_traits::{MozBrowserEvent, ScriptMsg as ConstellationMsg};
 use std::ascii::AsciiExt;
 use std::borrow::ToOwned;
 use std::cell::Cell;
diff --git a/components/script/dom/window.rs b/components/script/dom/window.rs
index 8ae52b9ccb0..df7f6a3faeb 100644
--- a/components/script/dom/window.rs
+++ b/components/script/dom/window.rs
@@ -43,8 +43,7 @@ use js::rust::Runtime;
 use layout_interface::{ContentBoxResponse, ContentBoxesResponse, ResolvedStyleResponse, ScriptReflow};
 use layout_interface::{LayoutChan, LayoutRPC, Msg, Reflow, ReflowQueryType};
 use libc;
-use msg::constellation_msg::{ConstellationChan, LoadData};
-use msg::constellation_msg::{MozBrowserEvent, PipelineId, SubpageId, WindowSizeData};
+use msg::constellation_msg::{ConstellationChan, LoadData, PipelineId, SubpageId, WindowSizeData};
 use msg::webdriver_msg::{WebDriverJSError, WebDriverJSResult};
 use net_traits::ResourceThread;
 use net_traits::image_cache_thread::{ImageCacheChan, ImageCacheThread};
@@ -57,9 +56,8 @@ use rustc_serialize::base64::{FromBase64, STANDARD, ToBase64};
 use script_thread::{DOMManipulationThreadSource, UserInteractionThreadSource, NetworkingThreadSource};
 use script_thread::{HistoryTraversalThreadSource, FileReadingThreadSource, SendableMainThreadScriptChan};
 use script_thread::{ScriptChan, ScriptPort, MainThreadScriptChan, MainThreadScriptMsg, RunnableWrapper};
-use script_traits::ScriptMsg as ConstellationMsg;
 use script_traits::{DocumentState, MsDuration, ScriptToCompositorMsg, TimerEvent, TimerEventId};
-use script_traits::{TimerEventRequest, TimerSource};
+use script_traits::{MozBrowserEvent, ScriptMsg as ConstellationMsg, TimerEventRequest, TimerSource};
 use selectors::parser::PseudoElement;
 use std::ascii::AsciiExt;
 use std::borrow::ToOwned;
diff --git a/components/script/script_thread.rs b/components/script/script_thread.rs
index 3e397f2b5f9..1b42f35d716 100644
--- a/components/script/script_thread.rs
+++ b/components/script/script_thread.rs
@@ -64,7 +64,7 @@ use layout_interface::{self, LayoutChan, NewLayoutThreadInfo, ScriptLayoutChan};
 use libc;
 use mem::heap_size_of_self_and_children;
 use msg::constellation_msg::{ConstellationChan, LoadData};
-use msg::constellation_msg::{MouseButton, MozBrowserEvent, PipelineId};
+use msg::constellation_msg::{MouseButton, PipelineId};
 use msg::constellation_msg::{PipelineNamespace};
 use msg::constellation_msg::{SubpageId, WindowSizeData};
 use msg::webdriver_msg::WebDriverScriptCommand;
@@ -81,7 +81,7 @@ use profile_traits::time::{self, ProfilerCategory, profile};
 use script_traits::CompositorEvent::{KeyEvent, MouseButtonEvent, MouseMoveEvent, ResizeEvent};
 use script_traits::CompositorEvent::{TouchEvent};
 use script_traits::{CompositorEvent, ConstellationControlMsg, EventResult};
-use script_traits::{InitialScriptState, MouseEventType, NewLayoutInfo};
+use script_traits::{InitialScriptState, MouseEventType, MozBrowserEvent, NewLayoutInfo};
 use script_traits::{LayoutMsg, OpaqueScriptLayoutChannel, ScriptMsg as ConstellationMsg};
 use script_traits::{ScriptThreadFactory, ScriptToCompositorMsg, TimerEvent, TimerEventRequest, TimerSource};
 use script_traits::{TouchEventType, TouchId};
diff --git a/components/script_traits/lib.rs b/components/script_traits/lib.rs
index 64e64e64ed9..d9fcba984ad 100644
--- a/components/script_traits/lib.rs
+++ b/components/script_traits/lib.rs
@@ -41,7 +41,7 @@ use ipc_channel::ipc::{IpcReceiver, IpcSender};
 use libc::c_void;
 use msg::constellation_msg::{ConstellationChan, Failure, PipelineId, WindowSizeData};
 use msg::constellation_msg::{Key, KeyModifiers, KeyState, LoadData, MouseButton};
-use msg::constellation_msg::{MozBrowserEvent, PipelineNamespaceId, SubpageId};
+use msg::constellation_msg::{PipelineNamespaceId, SubpageId};
 use msg::webdriver_msg::WebDriverScriptCommand;
 use net_traits::ResourceThread;
 use net_traits::image_cache_thread::ImageCacheThread;
@@ -371,3 +371,60 @@ pub struct IFrameLoadInfo {
     /// Sandbox type of this iframe
     pub sandbox: IFrameSandboxState,
 }
+
+// https://developer.mozilla.org/en-US/docs/Web/API/Using_the_Browser_API#Events
+/// The events fired in a Browser API context (`<iframe mozbrowser>`)
+#[derive(Deserialize, Serialize)]
+pub enum MozBrowserEvent {
+    /// Sent when the scroll position within a browser `<iframe>` changes.
+    AsyncScroll,
+    /// Sent when window.close() is called within a browser `<iframe>`.
+    Close,
+    /// Sent when a browser `<iframe>` tries to open a context menu. This allows
+    /// handling `<menuitem>` element available within the browser `<iframe>`'s content.
+    ContextMenu,
+    /// Sent when an error occurred while trying to load content within a browser `<iframe>`.
+    Error,
+    /// Sent when the favicon of a browser `<iframe>` changes.
+    IconChange(String, String, String),
+    /// Sent when the browser `<iframe>` has finished loading all its assets.
+    LoadEnd,
+    /// Sent when the browser `<iframe>` starts to load a new page.
+    LoadStart,
+    /// Sent when a browser `<iframe>`'s location changes.
+    LocationChange(String),
+    /// Sent when window.open() is called within a browser `<iframe>`.
+    OpenWindow,
+    /// Sent when the SSL state changes within a browser `<iframe>`.
+    SecurityChange,
+    /// Sent when alert(), confirm(), or prompt() is called within a browser `<iframe>`.
+    ShowModalPrompt(String, String, String, String), // TODO(simartin): Handle unblock()
+    /// Sent when the document.title changes within a browser `<iframe>`.
+    TitleChange(String),
+    /// Sent when an HTTP authentification is requested.
+    UsernameAndPasswordRequired,
+    /// Sent when a link to a search engine is found.
+    OpenSearch,
+}
+
+impl MozBrowserEvent {
+    /// Get the name of the event as a `& str`
+    pub fn name(&self) -> &'static str {
+        match *self {
+            MozBrowserEvent::AsyncScroll => "mozbrowserasyncscroll",
+            MozBrowserEvent::Close => "mozbrowserclose",
+            MozBrowserEvent::ContextMenu => "mozbrowsercontextmenu",
+            MozBrowserEvent::Error => "mozbrowsererror",
+            MozBrowserEvent::IconChange(_, _, _) => "mozbrowsericonchange",
+            MozBrowserEvent::LoadEnd => "mozbrowserloadend",
+            MozBrowserEvent::LoadStart => "mozbrowserloadstart",
+            MozBrowserEvent::LocationChange(_) => "mozbrowserlocationchange",
+            MozBrowserEvent::OpenWindow => "mozbrowseropenwindow",
+            MozBrowserEvent::SecurityChange => "mozbrowsersecuritychange",
+            MozBrowserEvent::ShowModalPrompt(_, _, _, _) => "mozbrowsershowmodalprompt",
+            MozBrowserEvent::TitleChange(_) => "mozbrowsertitlechange",
+            MozBrowserEvent::UsernameAndPasswordRequired => "mozbrowserusernameandpasswordrequired",
+            MozBrowserEvent::OpenSearch => "mozbrowseropensearch"
+        }
+    }
+}
diff --git a/components/script_traits/script_msg.rs b/components/script_traits/script_msg.rs
index 195976806a6..b4e8e587a3d 100644
--- a/components/script_traits/script_msg.rs
+++ b/components/script_traits/script_msg.rs
@@ -5,12 +5,12 @@
 use DocumentState;
 use IFrameLoadInfo;
 use MouseEventType;
+use MozBrowserEvent;
 use canvas_traits::CanvasMsg;
 use euclid::point::Point2D;
 use euclid::size::Size2D;
 use ipc_channel::ipc::IpcSender;
-use msg::constellation_msg::{AnimationState, NavigationDirection};
-use msg::constellation_msg::{Failure, MozBrowserEvent, PipelineId};
+use msg::constellation_msg::{AnimationState, NavigationDirection, Failure, PipelineId};
 use msg::constellation_msg::{LoadData, MouseButton, SubpageId};
 use offscreen_gl_context::GLContextAttributes;
 use style_traits::viewport::ViewportConstraints;