diff --git a/compiler/frontend/src/org/jetbrains/kotlin/cfg/ControlFlowInformationProvider.kt b/compiler/frontend/src/org/jetbrains/kotlin/cfg/ControlFlowInformationProvider.kt
index dce6163a8aa..b0662bd435f 100644
--- a/compiler/frontend/src/org/jetbrains/kotlin/cfg/ControlFlowInformationProvider.kt
+++ b/compiler/frontend/src/org/jetbrains/kotlin/cfg/ControlFlowInformationProvider.kt
@@ -671,7 +671,7 @@ class ControlFlowInformationProvider private constructor(
                 val mainFunctionDetector = MainFunctionDetector(trace.bindingContext, languageVersionSettings)
                 val isMain = owner is KtNamedFunction && mainFunctionDetector.isMain(owner)
                 val functionName = functionDescriptor.name
-                if (isMain && !languageVersionSettings.supportsFeature(LanguageFeature.ExtendedMainConvention)
+                if (isMain && !languageVersionSettings.supportsFeature(LanguageFeature.WarningOnMainUnusedParameter)
                     || functionDescriptor.isOverridableOrOverrides
                     || owner.hasModifier(KtTokens.OVERRIDE_KEYWORD)
                     || OperatorNameConventions.GET_VALUE == functionName
diff --git a/compiler/testData/diagnostics/tests/controlFlowAnalysis/mainWith12.kt b/compiler/testData/diagnostics/tests/controlFlowAnalysis/mainWith12.kt
deleted file mode 100644
index 802dad22d26..00000000000
--- a/compiler/testData/diagnostics/tests/controlFlowAnalysis/mainWith12.kt
+++ /dev/null
@@ -1,5 +0,0 @@
-// !LANGUAGE: -ExtendedMainConvention
-
-fun main(args: Array<String>) {
-
-}
\ No newline at end of file
diff --git a/compiler/testData/diagnostics/tests/controlFlowAnalysis/mainWith13.kt b/compiler/testData/diagnostics/tests/controlFlowAnalysis/mainWithWarningOnUnusedParam.kt
similarity index 55%
rename from compiler/testData/diagnostics/tests/controlFlowAnalysis/mainWith13.kt
rename to compiler/testData/diagnostics/tests/controlFlowAnalysis/mainWithWarningOnUnusedParam.kt
index b4e489385c5..c1712fe6746 100644
--- a/compiler/testData/diagnostics/tests/controlFlowAnalysis/mainWith13.kt
+++ b/compiler/testData/diagnostics/tests/controlFlowAnalysis/mainWithWarningOnUnusedParam.kt
@@ -1,3 +1,5 @@
+// !LANGUAGE: +WarningOnMainUnusedParameter
+
 fun main(<!UNUSED_PARAMETER!>args<!>: Array<String>) {
 
 }
\ No newline at end of file
diff --git a/compiler/testData/diagnostics/tests/controlFlowAnalysis/mainWith12.txt b/compiler/testData/diagnostics/tests/controlFlowAnalysis/mainWithWarningOnUnusedParam.txt
similarity index 100%
rename from compiler/testData/diagnostics/tests/controlFlowAnalysis/mainWith12.txt
rename to compiler/testData/diagnostics/tests/controlFlowAnalysis/mainWithWarningOnUnusedParam.txt
diff --git a/compiler/testData/diagnostics/tests/controlFlowAnalysis/mainWithoutWarningOnUnusedParam.kt b/compiler/testData/diagnostics/tests/controlFlowAnalysis/mainWithoutWarningOnUnusedParam.kt
new file mode 100644
index 00000000000..9ed477daa2e
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/controlFlowAnalysis/mainWithoutWarningOnUnusedParam.kt
@@ -0,0 +1,5 @@
+// !LANGUAGE: -WarningOnMainUnusedParameter
+
+fun main(args: Array<String>) {
+
+}
\ No newline at end of file
diff --git a/compiler/testData/diagnostics/tests/controlFlowAnalysis/mainWith13.txt b/compiler/testData/diagnostics/tests/controlFlowAnalysis/mainWithoutWarningOnUnusedParam.txt
similarity index 100%
rename from compiler/testData/diagnostics/tests/controlFlowAnalysis/mainWith13.txt
rename to compiler/testData/diagnostics/tests/controlFlowAnalysis/mainWithoutWarningOnUnusedParam.txt
diff --git a/compiler/testData/diagnostics/tests/redeclarations/RedeclarationMainInFile.kt b/compiler/testData/diagnostics/tests/redeclarations/RedeclarationMainInFile.kt
index 018f44808a6..8e526c11a0c 100644
--- a/compiler/testData/diagnostics/tests/redeclarations/RedeclarationMainInFile.kt
+++ b/compiler/testData/diagnostics/tests/redeclarations/RedeclarationMainInFile.kt
@@ -1,4 +1,4 @@
 // KT-9733 No error shown for 2 "main" functions in the same file
 
-<!CONFLICTING_OVERLOADS!>fun main(<!UNUSED_PARAMETER!>args<!>: Array<String>)<!> {}
-<!CONFLICTING_OVERLOADS!>fun main(<!UNUSED_PARAMETER!>args<!>: Array<String>)<!> {}
\ No newline at end of file
+<!CONFLICTING_OVERLOADS!>fun main(args: Array<String>)<!> {}
+<!CONFLICTING_OVERLOADS!>fun main(args: Array<String>)<!> {}
\ No newline at end of file
diff --git a/compiler/testData/diagnostics/tests/redeclarations/RedeclarationParameterlessMainInvalid.kt b/compiler/testData/diagnostics/tests/redeclarations/RedeclarationParameterlessMainInvalid.kt
index 3a65ef92bd7..e94e65a7955 100644
--- a/compiler/testData/diagnostics/tests/redeclarations/RedeclarationParameterlessMainInvalid.kt
+++ b/compiler/testData/diagnostics/tests/redeclarations/RedeclarationParameterlessMainInvalid.kt
@@ -1,7 +1,7 @@
 // FILE: a.kt
 <!CONFLICTING_OVERLOADS!>fun main()<!> {}
 
-suspend fun main(<!UNUSED_PARAMETER!>args<!>: Array<String>) {}
+suspend fun main(args: Array<String>) {}
 
 // FILE: b.kt
 <!CONFLICTING_OVERLOADS!>fun main()<!> {}
diff --git a/compiler/testData/diagnostics/testsWithStdLib/CallToMainRedeclaredInMultiFile.kt b/compiler/testData/diagnostics/testsWithStdLib/CallToMainRedeclaredInMultiFile.kt
index 697f33d54bc..35289768bc3 100644
--- a/compiler/testData/diagnostics/testsWithStdLib/CallToMainRedeclaredInMultiFile.kt
+++ b/compiler/testData/diagnostics/testsWithStdLib/CallToMainRedeclaredInMultiFile.kt
@@ -1,8 +1,8 @@
 // FILE: a.kt
-fun main(<!UNUSED_PARAMETER!>args<!>: Array<String>) {}
+fun main(args: Array<String>) {}
 
 // FILE: b.kt
-fun main(<!UNUSED_PARAMETER!>args<!>: Array<String>) {}
+fun main(args: Array<String>) {}
 
 // FILE: c.kt
 fun foo() { <!OVERLOAD_RESOLUTION_AMBIGUITY!>main<!>(arrayOf("a", "b")) }
\ No newline at end of file
diff --git a/compiler/tests/org/jetbrains/kotlin/checkers/DiagnosticsTestGenerated.java b/compiler/tests/org/jetbrains/kotlin/checkers/DiagnosticsTestGenerated.java
index b223bcb8d4c..48fe3bd4f51 100644
--- a/compiler/tests/org/jetbrains/kotlin/checkers/DiagnosticsTestGenerated.java
+++ b/compiler/tests/org/jetbrains/kotlin/checkers/DiagnosticsTestGenerated.java
@@ -3608,14 +3608,14 @@ public class DiagnosticsTestGenerated extends AbstractDiagnosticsTest {
                 runTest("compiler/testData/diagnostics/tests/controlFlowAnalysis/localObjectInConstructor.kt");
             }
 
-            @TestMetadata("mainWith12.kt")
-            public void testMainWith12() throws Exception {
-                runTest("compiler/testData/diagnostics/tests/controlFlowAnalysis/mainWith12.kt");
+            @TestMetadata("mainWithWarningOnUnusedParam.kt")
+            public void testMainWithWarningOnUnusedParam() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/controlFlowAnalysis/mainWithWarningOnUnusedParam.kt");
             }
 
-            @TestMetadata("mainWith13.kt")
-            public void testMainWith13() throws Exception {
-                runTest("compiler/testData/diagnostics/tests/controlFlowAnalysis/mainWith13.kt");
+            @TestMetadata("mainWithoutWarningOnUnusedParam.kt")
+            public void testMainWithoutWarningOnUnusedParam() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/controlFlowAnalysis/mainWithoutWarningOnUnusedParam.kt");
             }
 
             @TestMetadata("nestedTryFinally.kt")
diff --git a/compiler/tests/org/jetbrains/kotlin/checkers/javac/DiagnosticsUsingJavacTestGenerated.java b/compiler/tests/org/jetbrains/kotlin/checkers/javac/DiagnosticsUsingJavacTestGenerated.java
index 51718b58b54..4101eb647d2 100644
--- a/compiler/tests/org/jetbrains/kotlin/checkers/javac/DiagnosticsUsingJavacTestGenerated.java
+++ b/compiler/tests/org/jetbrains/kotlin/checkers/javac/DiagnosticsUsingJavacTestGenerated.java
@@ -3608,14 +3608,14 @@ public class DiagnosticsUsingJavacTestGenerated extends AbstractDiagnosticsUsing
                 runTest("compiler/testData/diagnostics/tests/controlFlowAnalysis/localObjectInConstructor.kt");
             }
 
-            @TestMetadata("mainWith12.kt")
-            public void testMainWith12() throws Exception {
-                runTest("compiler/testData/diagnostics/tests/controlFlowAnalysis/mainWith12.kt");
+            @TestMetadata("mainWithWarningOnUnusedParam.kt")
+            public void testMainWithWarningOnUnusedParam() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/controlFlowAnalysis/mainWithWarningOnUnusedParam.kt");
             }
 
-            @TestMetadata("mainWith13.kt")
-            public void testMainWith13() throws Exception {
-                runTest("compiler/testData/diagnostics/tests/controlFlowAnalysis/mainWith13.kt");
+            @TestMetadata("mainWithoutWarningOnUnusedParam.kt")
+            public void testMainWithoutWarningOnUnusedParam() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/controlFlowAnalysis/mainWithoutWarningOnUnusedParam.kt");
             }
 
             @TestMetadata("nestedTryFinally.kt")
diff --git a/compiler/util/src/org/jetbrains/kotlin/config/LanguageVersionSettings.kt b/compiler/util/src/org/jetbrains/kotlin/config/LanguageVersionSettings.kt
index 401f28fbe7c..2e60148cf91 100644
--- a/compiler/util/src/org/jetbrains/kotlin/config/LanguageVersionSettings.kt
+++ b/compiler/util/src/org/jetbrains/kotlin/config/LanguageVersionSettings.kt
@@ -91,6 +91,7 @@ enum class LanguageFeature(
     DslMarkerOnFunctionTypeReceiver(KOTLIN_1_4, kind = BUG_FIX),
     RestrictReturnStatementTarget(KOTLIN_1_4, kind = BUG_FIX),
     NoConstantValueAttributeForNonConstVals(KOTLIN_1_4, kind = BUG_FIX),
+    WarningOnMainUnusedParameter(KOTLIN_1_4),
 
     ProperVisibilityForCompanionObjectInstanceField(sinceVersion = null, kind = BUG_FIX),
     // Temporarily disabled, see KT-27084/KT-22379
diff --git a/idea/idea-analysis/src/org/jetbrains/kotlin/idea/facet/KotlinVersionInfoProvider.kt b/idea/idea-analysis/src/org/jetbrains/kotlin/idea/facet/KotlinVersionInfoProvider.kt
index 15e11f6aa67..a227f51bb55 100644
--- a/idea/idea-analysis/src/org/jetbrains/kotlin/idea/facet/KotlinVersionInfoProvider.kt
+++ b/idea/idea-analysis/src/org/jetbrains/kotlin/idea/facet/KotlinVersionInfoProvider.kt
@@ -77,6 +77,7 @@ fun getDefaultLanguageLevel(
 
 fun String?.toLanguageVersion(): LanguageVersion = when {
     this == null -> VersionView.RELEASED_VERSION
+    startsWith("1.4") -> LanguageVersion.KOTLIN_1_4
     startsWith("1.3") -> LanguageVersion.KOTLIN_1_3
     startsWith("1.2") -> LanguageVersion.KOTLIN_1_2
     startsWith("1.1") -> LanguageVersion.KOTLIN_1_1
diff --git a/idea/testData/checker/ExtensionFunctions.kt b/idea/testData/checker/ExtensionFunctions.kt
index 7747f4aebc5..ad332cce69c 100644
--- a/idea/testData/checker/ExtensionFunctions.kt
+++ b/idea/testData/checker/ExtensionFunctions.kt
@@ -50,7 +50,7 @@ fun Int.foo() = this
         fun Any?.equals1(<warning>other</warning> : Any?) : Boolean = true
         fun Any.equals2(<warning>other</warning> : Any?) : Boolean = true
 
-        fun main(<warning>args</warning>: Array<String>) {
+        fun main(args: Array<String>) {
 
             System.out.print(1)
 
diff --git a/idea/testData/checker/UnusedParameterInEntry13.kt b/idea/testData/checker/MainWithWarningOnUnusedParam.kt
similarity index 81%
rename from idea/testData/checker/UnusedParameterInEntry13.kt
rename to idea/testData/checker/MainWithWarningOnUnusedParam.kt
index c6c1faeb8dc..f503a2e9140 100644
--- a/idea/testData/checker/UnusedParameterInEntry13.kt
+++ b/idea/testData/checker/MainWithWarningOnUnusedParam.kt
@@ -1,3 +1,5 @@
+// LANGUAGE_VERSION: 1.4
+
 fun main(<warning descr="[UNUSED_PARAMETER] Parameter 'args' is never used">args</warning>: Array<String>) {
 
 }
\ No newline at end of file
diff --git a/idea/testData/checker/UnusedParameterInEntry12.kt b/idea/testData/checker/MainWithoutWarningOnUnusedParam.kt
similarity index 58%
rename from idea/testData/checker/UnusedParameterInEntry12.kt
rename to idea/testData/checker/MainWithoutWarningOnUnusedParam.kt
index 15eaac5c185..d2da7cd6cda 100644
--- a/idea/testData/checker/UnusedParameterInEntry12.kt
+++ b/idea/testData/checker/MainWithoutWarningOnUnusedParam.kt
@@ -1,4 +1,4 @@
-// LANGUAGE_VERSION: 1.2
+// LANGUAGE_VERSION: 1.3
 
 fun main(args: Array<String>) {
 
diff --git a/idea/testData/checker/infos/SmartCastToEnum.kt b/idea/testData/checker/infos/SmartCastToEnum.kt
index 9f862e127d4..3542cca816d 100644
--- a/idea/testData/checker/infos/SmartCastToEnum.kt
+++ b/idea/testData/checker/infos/SmartCastToEnum.kt
@@ -2,7 +2,7 @@ package test2
 
 <info descr="null">enum</info> class En { A, B, С }
 
-fun main(<warning>args</warning>: Array<String>) {
+fun main(args: Array<String>) {
     val en2: Any? = En.A
     if (en2 is En) {
         when (<info descr="Smart cast to test2.En">en2</info>) {
diff --git a/idea/testData/checker/regression/BadParseForClass.kt b/idea/testData/checker/regression/BadParseForClass.kt
index 4a5e73b7553..5ea57af0892 100644
--- a/idea/testData/checker/regression/BadParseForClass.kt
+++ b/idea/testData/checker/regression/BadParseForClass.kt
@@ -1,4 +1,4 @@
-fun main(<warning>args</warning>: Array<String>) {
+fun main(args: Array<String>) {
     String.class<EOLError descr="Name expected"></EOLError>
 }
 
diff --git a/idea/testData/checker/regression/DoubleDefine.kt b/idea/testData/checker/regression/DoubleDefine.kt
index 485ccf56394..a4716e628e9 100644
--- a/idea/testData/checker/regression/DoubleDefine.kt
+++ b/idea/testData/checker/regression/DoubleDefine.kt
@@ -38,7 +38,7 @@ fun evaluate(expr: StringBuilder, numbers: ArrayList<Int>): Int {
   return lhs
 }
 
-fun main(<warning>args</warning>: Array<String>) {
+fun main(args: Array<String>) {
   System.out.println("24 game")
   val numbers = ArrayList<Int>(4)
   val rnd = Random();
diff --git a/idea/testData/checker/regression/Jet69.kt b/idea/testData/checker/regression/Jet69.kt
index 87fbc11ef1a..a83894fbebe 100644
--- a/idea/testData/checker/regression/Jet69.kt
+++ b/idea/testData/checker/regression/Jet69.kt
@@ -4,7 +4,7 @@ fun parse(<warning>cmd</warning>: String): Command? { return null  }
 
 fun Any.<warning>equals</warning>(other : Any?) : Boolean = this === other
 
-fun main(<warning>args</warning>: Array<String>) {
+fun main(args: Array<String>) {
     val command = parse("")
     if (command == null) <warning>1</warning> // error on this line, but must be OK
 }
diff --git a/idea/testData/checker/regression/SpecififcityByReceiver.kt b/idea/testData/checker/regression/SpecififcityByReceiver.kt
index 5b476daebe6..5e1c2d4e331 100644
--- a/idea/testData/checker/regression/SpecififcityByReceiver.kt
+++ b/idea/testData/checker/regression/SpecififcityByReceiver.kt
@@ -1,6 +1,6 @@
 fun Any.<warning>equals</warning>(<warning>other</warning> : Any?) : Boolean = true
 
-fun main(<warning>args</warning>: Array<String>) {
+fun main(args: Array<String>) {
 
     val command : Any = 1
 
diff --git a/idea/tests/org/jetbrains/kotlin/checkers/PsiCheckerTestGenerated.java b/idea/tests/org/jetbrains/kotlin/checkers/PsiCheckerTestGenerated.java
index 7dd1f593515..2bc5687aa17 100644
--- a/idea/tests/org/jetbrains/kotlin/checkers/PsiCheckerTestGenerated.java
+++ b/idea/tests/org/jetbrains/kotlin/checkers/PsiCheckerTestGenerated.java
@@ -156,6 +156,16 @@ public class PsiCheckerTestGenerated extends AbstractPsiCheckerTest {
             runTest("idea/testData/checker/LocalObjects.kt");
         }
 
+        @TestMetadata("MainWithWarningOnUnusedParam.kt")
+        public void testMainWithWarningOnUnusedParam() throws Exception {
+            runTest("idea/testData/checker/MainWithWarningOnUnusedParam.kt");
+        }
+
+        @TestMetadata("MainWithoutWarningOnUnusedParam.kt")
+        public void testMainWithoutWarningOnUnusedParam() throws Exception {
+            runTest("idea/testData/checker/MainWithoutWarningOnUnusedParam.kt");
+        }
+
         @TestMetadata("MultipleBounds.kt")
         public void testMultipleBounds() throws Exception {
             runTest("idea/testData/checker/MultipleBounds.kt");
@@ -321,16 +331,6 @@ public class PsiCheckerTestGenerated extends AbstractPsiCheckerTest {
             runTest("idea/testData/checker/Unused.kt");
         }
 
-        @TestMetadata("UnusedParameterInEntry12.kt")
-        public void testUnusedParameterInEntry12() throws Exception {
-            runTest("idea/testData/checker/UnusedParameterInEntry12.kt");
-        }
-
-        @TestMetadata("UnusedParameterInEntry13.kt")
-        public void testUnusedParameterInEntry13() throws Exception {
-            runTest("idea/testData/checker/UnusedParameterInEntry13.kt");
-        }
-
         @TestMetadata("Variance.kt")
         public void testVariance() throws Exception {
             runTest("idea/testData/checker/Variance.kt");