diff --git a/components/net/image_cache_thread.rs b/components/net/image_cache_thread.rs
index 2fa8401990e..440ebd32100 100644
--- a/components/net/image_cache_thread.rs
+++ b/components/net/image_cache_thread.rs
@@ -5,7 +5,7 @@
 use immeta::load_from_buf;
 use ipc_channel::ipc::{self, IpcReceiver, IpcSender};
 use ipc_channel::router::ROUTER;
-use net_traits::{CoreResourceThread, NetworkError, ResponseAction, fetch_async, FetchResponseMsg, FetchMetadata};
+use net_traits::{CoreResourceThread, NetworkError, fetch_async, FetchResponseMsg, FetchMetadata, Metadata};
 use net_traits::image::base::{Image, ImageMetadata, PixelFormat, load_from_memory};
 use net_traits::image_cache_thread::{ImageCacheChan, ImageCacheCommand, ImageCacheThread, ImageState};
 use net_traits::image_cache_thread::{ImageCacheResult, ImageOrMetadataAvailable, ImageResponse, UsePlaceholder};
@@ -225,6 +225,15 @@ impl ImageListener {
     }
 }
 
+/// A legacy type that's mostly redundant with FetchResponseMsg.
+// FIXME(#13717): remove this type.
+#[derive(Deserialize, Serialize)]
+enum ResponseAction {
+    HeadersAvailable(Result<Metadata, NetworkError>),
+    DataAvailable(Vec<u8>),
+    ResponseComplete(Result<(), NetworkError>)
+}
+
 struct ResourceLoadInfo {
     action: ResponseAction,
     key: LoadKey,
diff --git a/components/net_traits/lib.rs b/components/net_traits/lib.rs
index eabad085ec3..39c5d0f8776 100644
--- a/components/net_traits/lib.rs
+++ b/components/net_traits/lib.rs
@@ -263,18 +263,6 @@ pub trait Action<Listener> {
     fn process(self, listener: &mut Listener);
 }
 
-/// Data for passing between threads/processes to indicate a particular action to
-/// take on a provided network listener.
-#[derive(Deserialize, Serialize)]
-pub enum ResponseAction {
-    /// Invoke headers_available
-    HeadersAvailable(Result<Metadata, NetworkError>),
-    /// Invoke data_available
-    DataAvailable(Vec<u8>),
-    /// Invoke response_complete
-    ResponseComplete(Result<(), NetworkError>)
-}
-
 impl<T: FetchResponseListener> Action<T> for FetchResponseMsg {
     /// Execute the default action on a provided listener.
     fn process(self, listener: &mut T) {