--- a/widget/windows/TSFTextStore.cpp
+++ b/widget/windows/TSFTextStore.cpp
@@ -854,16 +854,85 @@ public:
 
   bool IsATOKActive() const
   {
     // FYI: Name of ATOK includes the release year like "ATOK 2015".
     return StringBeginsWith(mActiveTIPKeyboardDescription,
                             NS_LITERAL_STRING("ATOK "));
   }
 
+  bool IsATOK2011Active() const
+  {
+    // {F9C24A5C-8A53-499D-9572-93B2FF582115}
+    static const GUID kGUID = {
+      0xF9C24A5C, 0x8A53, 0x499D,
+        { 0x95, 0x72, 0x93, 0xB2, 0xFF, 0x58, 0x21, 0x15 }
+    };
+    return mActiveTIPGUID == kGUID;
+  }
+
+  bool IsATOK2012Active() const
+  {
+    // {1DE01562-F445-401B-B6C3-E5B18DB79461}
+    static const GUID kGUID = {
+      0x1DE01562, 0xF445, 0x401B,
+        { 0xB6, 0xC3, 0xE5, 0xB1, 0x8D, 0xB7, 0x94, 0x61 }
+    };
+    return mActiveTIPGUID == kGUID;
+  }
+
+  bool IsATOK2013Active() const
+  {
+    // {3C4DB511-189A-4168-B6EA-BFD0B4C85615}
+    static const GUID kGUID = {
+      0x3C4DB511, 0x189A, 0x4168,
+        { 0xB6, 0xEA, 0xBF, 0xD0, 0xB4, 0xC8, 0x56, 0x15 }
+    };
+    return mActiveTIPGUID == kGUID;
+  }
+
+  bool IsATOK2014Active() const
+  {
+    // {4EF33B79-6AA9-4271-B4BF-9321C279381B}
+    static const GUID kGUID = {
+      0x4EF33B79, 0x6AA9, 0x4271,
+        { 0xB4, 0xBF, 0x93, 0x21, 0xC2, 0x79, 0x38, 0x1B }
+    };
+    return mActiveTIPGUID == kGUID;
+  }
+
+  bool IsATOK2015Active() const
+  {
+    // {EAB4DC00-CE2E-483D-A86A-E6B99DA9599A}
+    static const GUID kGUID = {
+      0xEAB4DC00, 0xCE2E, 0x483D,
+        { 0xA8, 0x6A, 0xE6, 0xB9, 0x9D, 0xA9, 0x59, 0x9A }
+    };
+    return mActiveTIPGUID == kGUID;
+  }
+
+  bool IsATOK2016Active() const
+  {
+    // {0B557B4C-5740-4110-A60A-1493FA10BF2B}
+    static const GUID kGUID = {
+      0x0B557B4C, 0x5740, 0x4110,
+        { 0xA6, 0x0A, 0x14, 0x93, 0xFA, 0x10, 0xBF, 0x2B }
+    };
+    return mActiveTIPGUID == kGUID;
+  }
+
+  // Note that ATOK 2011 - 2016 refers native caret position for deciding its
+  // popup window position.
+  bool IsATOKReferringNativeCaretActive() const
+  {
+    return IsATOKActive() &&
+           (IsATOK2011Active() || IsATOK2012Active() || IsATOK2013Active() ||
+            IsATOK2014Active() || IsATOK2015Active() || IsATOK2016Active());
+  }
+
   /****************************************************************************
    * Traditional Chinese TIP
    ****************************************************************************/
 
   bool IsMSChangJieActive() const
   {
     return mActiveTIPKeyboardDescription.EqualsLiteral("Microsoft ChangJie") ||
       mActiveTIPKeyboardDescription.Equals(
@@ -1189,17 +1258,17 @@ StaticRefPtr<ITfKeystrokeMgr> TSFTextSto
 StaticRefPtr<ITfDisplayAttributeMgr> TSFTextStore::sDisplayAttrMgr;
 StaticRefPtr<ITfCategoryMgr> TSFTextStore::sCategoryMgr;
 StaticRefPtr<ITfDocumentMgr> TSFTextStore::sDisabledDocumentMgr;
 StaticRefPtr<ITfContext> TSFTextStore::sDisabledContext;
 StaticRefPtr<ITfInputProcessorProfiles> TSFTextStore::sInputProcessorProfiles;
 StaticRefPtr<TSFTextStore> TSFTextStore::sEnabledTextStore;
 DWORD TSFTextStore::sClientId  = 0;
 
-bool TSFTextStore::sCreateNativeCaretForATOK = false;
+bool TSFTextStore::sCreateNativeCaretForLegacyATOK = false;
 bool TSFTextStore::sDoNotReturnNoLayoutErrorToMSSimplifiedTIP = false;
 bool TSFTextStore::sDoNotReturnNoLayoutErrorToMSTraditionalTIP = false;
 bool TSFTextStore::sDoNotReturnNoLayoutErrorToFreeChangJie = false;
 bool TSFTextStore::sDoNotReturnNoLayoutErrorToEasyChangjei = false;
 bool TSFTextStore::sDoNotReturnNoLayoutErrorToMSJapaneseIMEAtFirstChar = false;
 bool TSFTextStore::sDoNotReturnNoLayoutErrorToMSJapaneseIMEAtCaret = false;
 bool TSFTextStore::sHackQueryInsertForMSSimplifiedTIP = false;
 bool TSFTextStore::sHackQueryInsertForMSTraditionalTIP = false;
@@ -3833,20 +3902,22 @@ TSFTextStore::GetTextExt(TsViewCookie vc
             event.mReply.mRect.XMost(), event.mReply.mRect.YMost());
   if (!::IntersectRect(prc, prc, &textRect))
     // Text is not visible
     ::SetRectEmpty(prc);
 
   // not equal if text rect was clipped
   *pfClipped = !::EqualRect(prc, &textRect);
 
-  // ATOK refers native caret position and size on Desktop applications for
-  // deciding candidate window.  Therefore, we need to create native caret
-  // for hacking the bug.
-  if (sCreateNativeCaretForATOK && kSink->IsATOKActive() &&
+  // ATOK 2011 - 2016 refers native caret position and size on windows whose
+  // class name is one of Mozilla's windows for deciding candidate window
+  // position.  Therefore, we need to create native caret only when ATOK 2011 -
+  // 2016 is active.
+  if (sCreateNativeCaretForLegacyATOK &&
+      kSink->IsATOKReferringNativeCaretActive() &&
       mComposition.IsComposing() &&
       mComposition.mStart <= acpStart && mComposition.EndOffset() >= acpStart &&
       mComposition.mStart <= acpEnd && mComposition.EndOffset() >= acpEnd) {
     CreateNativeCaret();
   }
 
   MOZ_LOG(sTextStoreLog, LogLevel::Info,
     ("0x%p   TSFTextStore::GetTextExt() succeeded: "
@@ -5673,17 +5744,17 @@ TSFTextStore::Initialize()
   sThreadMgr = threadMgr;
   sMessagePump = messagePump;
   sKeystrokeMgr = keystrokeMgr;
   sDisplayAttrMgr = displayAttributeMgr;
   sCategoryMgr = categoryMgr;
   sDisabledDocumentMgr = disabledDocumentMgr;
   sDisabledContext = disabledContext;
 
-  sCreateNativeCaretForATOK =
+  sCreateNativeCaretForLegacyATOK =
     Preferences::GetBool("intl.tsf.hack.atok.create_native_caret", true);
   sDoNotReturnNoLayoutErrorToMSSimplifiedTIP =
     Preferences::GetBool(
       "intl.tsf.hack.ms_simplified_chinese.do_not_return_no_layout_error",
       true);
   sDoNotReturnNoLayoutErrorToMSTraditionalTIP =
     Preferences::GetBool(
       "intl.tsf.hack.ms_traditional_chinese.do_not_return_no_layout_error",
@@ -5708,24 +5779,24 @@ TSFTextStore::Initialize()
   sHackQueryInsertForMSTraditionalTIP =
     Preferences::GetBool(
       "intl.tsf.hack.ms_traditional_chinese.query_insert_result", true);
 
   MOZ_LOG(sTextStoreLog, LogLevel::Info,
     ("  TSFTextStore::Initialize(), sThreadMgr=0x%p, "
      "sClientId=0x%08X, sDisplayAttrMgr=0x%p, "
      "sCategoryMgr=0x%p, sDisabledDocumentMgr=0x%p, sDisabledContext=%p, "
-     "sCreateNativeCaretForATOK=%s, "
+     "sCreateNativeCaretForLegacyATOK=%s, "
      "sDoNotReturnNoLayoutErrorToFreeChangJie=%s, "
      "sDoNotReturnNoLayoutErrorToEasyChangjei=%s, "
      "sDoNotReturnNoLayoutErrorToMSJapaneseIMEAtFirstChar=%s, "
      "sDoNotReturnNoLayoutErrorToMSJapaneseIMEAtCaret=%s",
      sThreadMgr.get(), sClientId, sDisplayAttrMgr.get(),
      sCategoryMgr.get(), sDisabledDocumentMgr.get(), sDisabledContext.get(),
-     GetBoolName(sCreateNativeCaretForATOK),
+     GetBoolName(sCreateNativeCaretForLegacyATOK),
      GetBoolName(sDoNotReturnNoLayoutErrorToFreeChangJie),
      GetBoolName(sDoNotReturnNoLayoutErrorToEasyChangjei),
      GetBoolName(sDoNotReturnNoLayoutErrorToMSJapaneseIMEAtFirstChar),
      GetBoolName(sDoNotReturnNoLayoutErrorToMSJapaneseIMEAtCaret)));
 }
 
 // static
 void

--- a/widget/windows/TSFTextStore.h
+++ b/widget/windows/TSFTextStore.h
@@ -980,17 +980,17 @@ protected:
   static StaticRefPtr<ITfContext> sDisabledContext;
 
   static StaticRefPtr<ITfInputProcessorProfiles> sInputProcessorProfiles;
 
   // TSF client ID for the current application
   static DWORD sClientId;
 
   // Enables/Disables hack for specific TIP.
-  static bool sCreateNativeCaretForATOK;
+  static bool sCreateNativeCaretForLegacyATOK;
   static bool sDoNotReturnNoLayoutErrorToMSSimplifiedTIP;
   static bool sDoNotReturnNoLayoutErrorToMSTraditionalTIP;
   static bool sDoNotReturnNoLayoutErrorToFreeChangJie;
   static bool sDoNotReturnNoLayoutErrorToEasyChangjei;
   static bool sDoNotReturnNoLayoutErrorToMSJapaneseIMEAtFirstChar;
   static bool sDoNotReturnNoLayoutErrorToMSJapaneseIMEAtCaret;
   static bool sHackQueryInsertForMSSimplifiedTIP;
   static bool sHackQueryInsertForMSTraditionalTIP;