diff --git a/intl/build/nsI18nModule.cpp b/intl/build/nsI18nModule.cpp
index df28bb2d1e0c..6c992c44820e 100644
--- a/intl/build/nsI18nModule.cpp
+++ b/intl/build/nsI18nModule.cpp
@@ -13,7 +13,6 @@
 // unicharutil
 #include "nsCategoryImp.h"
 #include "nsUnicharUtilCIID.h"
-#include "nsCaseConversionImp2.h"
 #include "nsEntityConverter.h"
 #include "nsSaveAsCharset.h"
 #include "nsUnicodeNormalizer.h"
@@ -33,7 +32,6 @@ NS_GENERIC_FACTORY_CONSTRUCTOR(nsSampleWordBreaker)
 NS_GENERIC_FACTORY_CONSTRUCTOR_INIT(nsStringBundleService, Init)
 NS_GENERIC_FACTORY_CONSTRUCTOR_INIT(nsStringBundleTextOverride, Init)
 
-NS_GENERIC_FACTORY_CONSTRUCTOR(nsCaseConversionImp2)
 NS_GENERIC_FACTORY_SINGLETON_CONSTRUCTOR(nsCategoryImp,
                                          nsCategoryImp::GetInstance)
 NS_GENERIC_FACTORY_CONSTRUCTOR(nsEntityConverter)
@@ -44,7 +42,6 @@ NS_DEFINE_NAMED_CID(MOZ_LOCALESERVICE_CID);
 NS_DEFINE_NAMED_CID(MOZ_OSPREFERENCES_CID);
 NS_DEFINE_NAMED_CID(NS_LBRK_CID);
 NS_DEFINE_NAMED_CID(NS_WBRK_CID);
-NS_DEFINE_NAMED_CID(NS_UNICHARUTIL_CID);
 NS_DEFINE_NAMED_CID(NS_UNICHARCATEGORY_CID);
 NS_DEFINE_NAMED_CID(NS_ENTITYCONVERTER_CID);
 NS_DEFINE_NAMED_CID(NS_SAVEASCHARSET_CID);
@@ -62,7 +59,6 @@ static const mozilla::Module::CIDEntry kIntlCIDs[] = {
     { &kMOZ_OSPREFERENCES_CID, false, nullptr, mozilla::intl::OSPreferencesConstructor },
     { &kNS_LBRK_CID, false, nullptr, nsJISx4051LineBreakerConstructor },
     { &kNS_WBRK_CID, false, nullptr, nsSampleWordBreakerConstructor },
-    { &kNS_UNICHARUTIL_CID, false, nullptr, nsCaseConversionImp2Constructor },
     { &kNS_UNICHARCATEGORY_CID, false, nullptr, nsCategoryImpConstructor },
     { &kNS_ENTITYCONVERTER_CID, false, nullptr, nsEntityConverterConstructor },
     { &kNS_SAVEASCHARSET_CID, false, nullptr, nsSaveAsCharsetConstructor },
@@ -82,7 +78,6 @@ static const mozilla::Module::ContractIDEntry kIntlContracts[] = {
     { MOZ_OSPREFERENCES_CONTRACTID, &kMOZ_OSPREFERENCES_CID },
     { NS_LBRK_CONTRACTID, &kNS_LBRK_CID },
     { NS_WBRK_CONTRACTID, &kNS_WBRK_CID },
-    { NS_UNICHARUTIL_CONTRACTID, &kNS_UNICHARUTIL_CID },
     { NS_UNICHARCATEGORY_CONTRACTID, &kNS_UNICHARCATEGORY_CID },
     { NS_ENTITYCONVERTER_CONTRACTID, &kNS_ENTITYCONVERTER_CID },
     { NS_SAVEASCHARSET_CONTRACTID, &kNS_SAVEASCHARSET_CID },
diff --git a/intl/unicharutil/moz.build b/intl/unicharutil/moz.build
index 461fd255efaf..03db78d1dde6 100644
--- a/intl/unicharutil/moz.build
+++ b/intl/unicharutil/moz.build
@@ -16,14 +16,12 @@ XPIDL_SOURCES += [
 XPIDL_MODULE = 'unicharutil'
 
 EXPORTS += [
-    'nsICaseConversion.h',
     'nsIUGenCategory.h',
     'nsUnicharUtilCIID.h',
     'nsUnicodeNormalizer.h',
 ]
 
 UNIFIED_SOURCES += [
-    'nsCaseConversionImp2.cpp',
     'nsCategoryImp.cpp',
     'nsEntityConverter.cpp',
     'nsSaveAsCharset.cpp',
diff --git a/intl/unicharutil/nsCaseConversionImp2.cpp b/intl/unicharutil/nsCaseConversionImp2.cpp
deleted file mode 100644
index 61750213742d..000000000000
--- a/intl/unicharutil/nsCaseConversionImp2.cpp
+++ /dev/null
@@ -1,62 +0,0 @@
-/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-#include "nsCaseConversionImp2.h"
-#include "nsUnicharUtils.h"
-
-NS_IMETHODIMP_(MozExternalRefCountType) nsCaseConversionImp2::AddRef(void)
-{
-  return (MozExternalRefCountType)1;
-}
-
-NS_IMETHODIMP_(MozExternalRefCountType) nsCaseConversionImp2::Release(void)
-{
-  return (MozExternalRefCountType)1;
-}
-
-NS_IMPL_QUERY_INTERFACE(nsCaseConversionImp2, nsICaseConversion)
-
-NS_IMETHODIMP nsCaseConversionImp2::ToUpper(char16_t aChar, char16_t* aReturn)
-{
-  *aReturn = ToUpperCase(aChar);
-  return NS_OK;
-}
-
-NS_IMETHODIMP nsCaseConversionImp2::ToLower(char16_t aChar, char16_t* aReturn)
-{
-  *aReturn = ToLowerCase(aChar);
-  return NS_OK;
-}
-
-NS_IMETHODIMP nsCaseConversionImp2::ToTitle(char16_t aChar, char16_t* aReturn)
-{
-  *aReturn = ToTitleCase(aChar);
-  return NS_OK;
-}
-
-NS_IMETHODIMP nsCaseConversionImp2::ToUpper(const char16_t* anArray,
-                                         char16_t* aReturn,
-                                         uint32_t aLen)
-{
-  ToUpperCase(anArray, aReturn, aLen);
-  return NS_OK;
-}
-
-NS_IMETHODIMP nsCaseConversionImp2::ToLower(const char16_t* anArray,
-                                         char16_t* aReturn,
-                                         uint32_t aLen)
-{
-  ToLowerCase(anArray, aReturn, aLen);
-  return NS_OK;
-}
-
-NS_IMETHODIMP
-nsCaseConversionImp2::CaseInsensitiveCompare(const char16_t *aLeft,
-                                             const char16_t *aRight,
-                                             uint32_t aCount, int32_t* aResult)
-{
-  *aResult = ::CaseInsensitiveCompare(aLeft, aRight, aCount);
-  return NS_OK;
-}
diff --git a/intl/unicharutil/nsCaseConversionImp2.h b/intl/unicharutil/nsCaseConversionImp2.h
deleted file mode 100644
index 6521ae832ea6..000000000000
--- a/intl/unicharutil/nsCaseConversionImp2.h
+++ /dev/null
@@ -1,35 +0,0 @@
-/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-#ifndef nsCaseConversionImp2_h__
-#define nsCaseConversionImp2_h__
-
-#include "nscore.h"
-#include "nsISupports.h"
-
-#include "nsICaseConversion.h"
-
-class nsCaseConversionImp2 : public nsICaseConversion { 
-  NS_DECL_THREADSAFE_ISUPPORTS 
-
-public:
-  virtual ~nsCaseConversionImp2() { }
-
-  static nsCaseConversionImp2* GetInstance();
-
-  NS_IMETHOD ToUpper(char16_t aChar, char16_t* aReturn) override;
-
-  NS_IMETHOD ToLower(char16_t aChar, char16_t* aReturn) override;
-
-  NS_IMETHOD ToTitle(char16_t aChar, char16_t* aReturn) override;
-
-  NS_IMETHOD ToUpper(const char16_t* anArray, char16_t* aReturn, uint32_t aLen) override;
-
-  NS_IMETHOD ToLower(const char16_t* anArray, char16_t* aReturn, uint32_t aLen) override;
-
-  NS_IMETHOD CaseInsensitiveCompare(const char16_t* aLeft, const char16_t* aRight, uint32_t aLength, int32_t *aResult) override;
-};
-
-#endif
diff --git a/intl/unicharutil/nsICaseConversion.h b/intl/unicharutil/nsICaseConversion.h
deleted file mode 100644
index 06d5dc5a1f09..000000000000
--- a/intl/unicharutil/nsICaseConversion.h
+++ /dev/null
@@ -1,45 +0,0 @@
-/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-#ifndef nsICaseConversion_h__
-#define nsICaseConversion_h__
-
-
-#include "nsISupports.h"
-#include "nscore.h"
-
-// {07D3D8E0-9614-11d2-B3AD-00805F8A6670}
-#define NS_ICASECONVERSION_IID \
-{ 0x7d3d8e0, 0x9614, 0x11d2, \
-    { 0xb3, 0xad, 0x0, 0x80, 0x5f, 0x8a, 0x66, 0x70 } }
-
-class nsICaseConversion : public nsISupports {
-
-public: 
-
-  NS_DECLARE_STATIC_IID_ACCESSOR(NS_ICASECONVERSION_IID)
-
-  // Convert one Unicode character into upper case
-  NS_IMETHOD ToUpper( char16_t aChar, char16_t* aReturn) = 0;
-
-  // Convert one Unicode character into lower case
-  NS_IMETHOD ToLower( char16_t aChar, char16_t* aReturn) = 0;
-
-  // Convert one Unicode character into title case
-  NS_IMETHOD ToTitle( char16_t aChar, char16_t* aReturn) = 0;
-
-  // Convert an array of Unicode characters into upper case
-  NS_IMETHOD ToUpper( const char16_t* anArray, char16_t* aReturn, uint32_t aLen) = 0;
-
-  // Convert an array of Unicode characters into lower case
-  NS_IMETHOD ToLower( const char16_t* anArray, char16_t* aReturn, uint32_t aLen) = 0;
-
-  // case-insensitive char16_t* comparison - aResult returns similar
-  // to strcasecmp
-  NS_IMETHOD CaseInsensitiveCompare(const char16_t* aLeft, const char16_t* aRight, uint32_t aLength, int32_t* aResult) = 0;
-};
-
-NS_DEFINE_STATIC_IID_ACCESSOR(nsICaseConversion, NS_ICASECONVERSION_IID)
-
-#endif  /* nsICaseConversion_h__ */
diff --git a/intl/unicharutil/nsUnicharUtilCIID.h b/intl/unicharutil/nsUnicharUtilCIID.h
index 16aad35fe9bd..43783dbb77ab 100644
--- a/intl/unicharutil/nsUnicharUtilCIID.h
+++ b/intl/unicharutil/nsUnicharUtilCIID.h
@@ -9,12 +9,6 @@
 #include "nsISupports.h"
 #include "nscore.h"
 
-#define NS_UNICHARUTIL_CID \
-{ 0xcc10c750, 0x9ec3, 0x11d2, \
-  { 0xb3, 0xae, 0x0, 0x80, 0x5f, 0x8a, 0x66, 0x70 } }
-
-#define NS_UNICHARUTIL_CONTRACTID "@mozilla.org/intl/unicharutil;1"
-
 #define NS_UNICHARCATEGORY_CID \
 { 0x748a1132, 0x671a, 0x409a, \
   { 0x8d, 0x1d, 0xf1, 0xcd, 0xf6, 0xb3, 0xa6, 0xb4 } }