diff --git a/src/node_i18n.cc b/src/node_i18n.cc
index 06ecf85eab9234..2e7801fa896ef7 100644
--- a/src/node_i18n.cc
+++ b/src/node_i18n.cc
@@ -435,8 +435,7 @@ bool InitializeICUDirectory(const std::string& path) {
 
 int32_t ToUnicode(MaybeStackBuffer<char>* buf,
                   const char* input,
-                  size_t length,
-                  bool lenient) {
+                  size_t length) {
   UErrorCode status = U_ZERO_ERROR;
   uint32_t options = UIDNA_DEFAULT;
   options |= UIDNA_NONTRANSITIONAL_TO_UNICODE;
@@ -461,29 +460,7 @@ int32_t ToUnicode(MaybeStackBuffer<char>* buf,
                                   &status);
   }
 
-  // UTS #46's ToUnicode operation applies no validation of domain name length
-  // (nor a flag requesting it to do so, like VerifyDnsLength for ToASCII). For
-  // that reason, unlike ToASCII below, ICU4C correctly accepts long domain
-  // names. However, ICU4C still sets the EMPTY_LABEL error in contrary to UTS
-  // #46. Therefore, explicitly filters out that error here.
-  info.errors &= ~UIDNA_ERROR_EMPTY_LABEL;
-
-  // These error conditions are mandated unconditionally by UTS #46 version
-  // 9.0.0 (rev. 17), but were found to be incompatible with many actual domain
-  // names in the wild. As such, in the current UTS #46 draft (rev. 18) these
-  // checks are made optional depending on the CheckHyphens flag, which will be
-  // disabled in WHATWG URL's "domain to unicode" algorithm as soon as the UTS
-  // #46 draft becomes standard.
-  // Refs:
-  // - https://github.com/whatwg/url/issues/53
-  // - http://www.unicode.org/review/pri317/
-  // - http://www.unicode.org/reports/tr46/tr46-18.html
-  // - https://www.icann.org/news/announcement-2000-01-07-en
-  info.errors &= ~UIDNA_ERROR_HYPHEN_3_4;
-  info.errors &= ~UIDNA_ERROR_LEADING_HYPHEN;
-  info.errors &= ~UIDNA_ERROR_TRAILING_HYPHEN;
-
-  if (U_FAILURE(status) || (!lenient && info.errors != 0)) {
+  if (U_FAILURE(status)) {
     len = -1;
     buf->SetLength(0);
   } else {
@@ -563,11 +540,9 @@ static void ToUnicode(const FunctionCallbackInfo<Value>& args) {
   CHECK_GE(args.Length(), 1);
   CHECK(args[0]->IsString());
   Utf8Value val(env->isolate(), args[0]);
-  // optional arg
-  bool lenient = args[1]->BooleanValue(env->context()).FromJust();
 
   MaybeStackBuffer<char> buf;
-  int32_t len = ToUnicode(&buf, *val, val.length(), lenient);
+  int32_t len = ToUnicode(&buf, *val, val.length());
 
   if (len < 0) {
     return env->ThrowError("Cannot convert name to Unicode");
diff --git a/src/node_i18n.h b/src/node_i18n.h
index 78e18fdb370c94..cc1f3e6ea53569 100644
--- a/src/node_i18n.h
+++ b/src/node_i18n.h
@@ -43,8 +43,7 @@ int32_t ToASCII(MaybeStackBuffer<char>* buf,
                 bool lenient = false);
 int32_t ToUnicode(MaybeStackBuffer<char>* buf,
                   const char* input,
-                  size_t length,
-                  bool lenient = false);
+                  size_t length);
 
 }  // namespace i18n
 }  // namespace node
diff --git a/test/fixtures/url-idna.js b/test/fixtures/url-idna.js
index 9a6a206abbaf21..41f12edc6c2f7d 100644
--- a/test/fixtures/url-idna.js
+++ b/test/fixtures/url-idna.js
@@ -219,15 +219,6 @@ module.exports = {
     {
       url: '\ufffd.com',
       mode: 'ascii'
-    },
-    {
-      url: '\ufffd.com',
-      mode: 'unicode'
-    },
-    // invalid Punycode
-    {
-      url: 'xn---abc.com',
-      mode: 'unicode'
     }
   ]
 }