diff --git a/Source/WebKitLegacy/mac/ChangeLog b/Source/WebKitLegacy/mac/ChangeLog
index 93f7ee3..382a5a1 100644
--- a/Source/WebKitLegacy/mac/ChangeLog
+++ b/Source/WebKitLegacy/mac/ChangeLog
@@ -1,5 +1,12 @@
 2019-10-16  Chris Dumez  <cdumez@apple.com>
 
+        Unreviewed, fix iOS Debug build after r251220.
+
+        * WebView/WebView.mm:
+        (-[WebView _preferencesChanged:]):
+
+2019-10-16  Chris Dumez  <cdumez@apple.com>
+
         Rename PageCache to BackForwardCache
         https://bugs.webkit.org/show_bug.cgi?id=203048
 
diff --git a/Source/WebKitLegacy/mac/WebView/WebView.mm b/Source/WebKitLegacy/mac/WebView/WebView.mm
index 4eea31d..9415dd2 100644
--- a/Source/WebKitLegacy/mac/WebView/WebView.mm
+++ b/Source/WebKitLegacy/mac/WebView/WebView.mm
@@ -3041,7 +3041,7 @@
     settings.setPasswordEchoEnabled([preferences _allowPasswordEcho]);
     settings.setPasswordEchoDurationInSeconds([preferences _passwordEchoDuration]);
 
-    ASSERT_WITH_MESSAGE(settings.pageCacheSupportsPlugins(), "PageCacheSupportsPlugins should be enabled on iOS.");
+    ASSERT_WITH_MESSAGE(settings.backForwardCacheSupportsPlugins(), "BackForwardCacheSupportsPlugins should be enabled on iOS.");
     settings.setDelegatesPageScaling(true);
 
 #if ENABLE(TEXT_AUTOSIZING)