diff --git a/src/__phutil_library_map__.php b/src/__phutil_library_map__.php
index 5a86c6b01a..46af533643 100644
--- a/src/__phutil_library_map__.php
+++ b/src/__phutil_library_map__.php
@@ -52,6 +52,7 @@ phutil_register_library_map(array(
     'AphrontFormToggleButtonsControl' => 'view/form/control/AphrontFormToggleButtonsControl.php',
     'AphrontFormTokenizerControl' => 'view/form/control/AphrontFormTokenizerControl.php',
     'AphrontFormView' => 'view/form/AphrontFormView.php',
+    'AphrontHTMLResponse' => 'aphront/response/AphrontHTMLResponse.php',
     'AphrontHTTPSink' => 'aphront/sink/AphrontHTTPSink.php',
     'AphrontHTTPSinkTestCase' => 'aphront/sink/__tests__/AphrontHTTPSinkTestCase.php',
     'AphrontHeadsupActionListView' => 'view/layout/headsup/AphrontHeadsupActionListView.php',
@@ -1317,8 +1318,8 @@ phutil_register_library_map(array(
   array(
     'Aphront304Response' => 'AphrontResponse',
     'Aphront400Response' => 'AphrontResponse',
-    'Aphront403Response' => 'AphrontWebpageResponse',
-    'Aphront404Response' => 'AphrontWebpageResponse',
+    'Aphront403Response' => 'AphrontHTMLResponse',
+    'Aphront404Response' => 'AphrontHTMLResponse',
     'AphrontAjaxResponse' => 'AphrontResponse',
     'AphrontAttachedFileView' => 'AphrontView',
     'AphrontCSRFException' => 'AphrontException',
@@ -1355,6 +1356,7 @@ phutil_register_library_map(array(
     'AphrontFormToggleButtonsControl' => 'AphrontFormControl',
     'AphrontFormTokenizerControl' => 'AphrontFormControl',
     'AphrontFormView' => 'AphrontView',
+    'AphrontHTMLResponse' => 'AphrontResponse',
     'AphrontHTTPSinkTestCase' => 'PhabricatorTestCase',
     'AphrontHeadsupActionListView' => 'AphrontView',
     'AphrontHeadsupActionView' => 'AphrontView',
@@ -1386,7 +1388,7 @@ phutil_register_library_map(array(
     'AphrontTokenizerTemplateView' => 'AphrontView',
     'AphrontTypeaheadTemplateView' => 'AphrontView',
     'AphrontUsageException' => 'AphrontException',
-    'AphrontWebpageResponse' => 'AphrontResponse',
+    'AphrontWebpageResponse' => 'AphrontHTMLResponse',
     'CelerityPhabricatorResourceController' => 'CelerityResourceController',
     'CelerityResourceController' => 'PhabricatorController',
     'CelerityResourceGraph' => 'AbstractDirectedGraph',
diff --git a/src/aphront/response/Aphront403Response.php b/src/aphront/response/Aphront403Response.php
index f2eafd719d..350c0e3a38 100644
--- a/src/aphront/response/Aphront403Response.php
+++ b/src/aphront/response/Aphront403Response.php
@@ -3,7 +3,7 @@
 /**
  * @group aphront
  */
-final class Aphront403Response extends AphrontWebpageResponse {
+final class Aphront403Response extends AphrontHTMLResponse {
 
   private $forbiddenText;
   public function setForbiddenText($text) {
diff --git a/src/aphront/response/Aphront404Response.php b/src/aphront/response/Aphront404Response.php
index 69b3603b3f..2821012fc4 100644
--- a/src/aphront/response/Aphront404Response.php
+++ b/src/aphront/response/Aphront404Response.php
@@ -3,7 +3,7 @@
 /**
  * @group aphront
  */
-final class Aphront404Response extends AphrontWebpageResponse {
+final class Aphront404Response extends AphrontHTMLResponse {
 
   public function getHTTPResponseCode() {
     return 404;
diff --git a/src/aphront/response/AphrontHTMLResponse.php b/src/aphront/response/AphrontHTMLResponse.php
new file mode 100644
index 0000000000..4448fcdf12
--- /dev/null
+++ b/src/aphront/response/AphrontHTMLResponse.php
@@ -0,0 +1,16 @@
+<?php
+
+/**
+ * @group aphront
+ */
+abstract class AphrontHTMLResponse extends AphrontResponse {
+
+  public function getHeaders() {
+    $headers = array(
+      array('Content-Type', 'text/html; charset=UTF-8'),
+    );
+    $headers = array_merge(parent::getHeaders(), $headers);
+    return $headers;
+  }
+
+}
diff --git a/src/aphront/response/AphrontWebpageResponse.php b/src/aphront/response/AphrontWebpageResponse.php
index e800d1122f..4083b1be88 100644
--- a/src/aphront/response/AphrontWebpageResponse.php
+++ b/src/aphront/response/AphrontWebpageResponse.php
@@ -1,11 +1,9 @@
 <?php
 
 /**
- * TODO: Should be final, but isn't because of Aphront403Response / 404Response.
- *
  * @group aphront
  */
-class AphrontWebpageResponse extends AphrontResponse {
+final class AphrontWebpageResponse extends AphrontHTMLResponse {
 
   private $content;
 
@@ -18,12 +16,4 @@ class AphrontWebpageResponse extends AphrontResponse {
     return $this->content;
   }
 
-  public function getHeaders() {
-    $headers = array(
-      array('Content-Type', 'text/html; charset=UTF-8'),
-    );
-    $headers = array_merge(parent::getHeaders(), $headers);
-    return $headers;
-  }
-
 }