diff --git a/intl/unicharutil/util/ICUUtils.cpp b/intl/unicharutil/util/ICUUtils.cpp
index 473e07aedfa5..c143d3d412c9 100644
--- a/intl/unicharutil/util/ICUUtils.cpp
+++ b/intl/unicharutil/util/ICUUtils.cpp
@@ -213,6 +213,34 @@ mCurrentFallbackIndex
 =
 2
 ;
+if
+(
+mContent
+-
+>
+OwnerDoc
+-
+>
+ShouldResistFingerprinting
+(
+RFPTarget
+:
+:
+JSLocale
+)
+)
+{
+return
+NS_Atomize
+(
+"
+en
+-
+US
+"
+)
+;
+}
 nsAutoCString
 appLocale
 ;