diff --git a/compiler/testData/diagnostics/testsWithJsStdLib/name/externalClassInheritance.kt b/compiler/testData/diagnostics/testsWithJsStdLib/name/externalClassInheritance.kt
index 9b127f6f8be..4670627b275 100644
--- a/compiler/testData/diagnostics/testsWithJsStdLib/name/externalClassInheritance.kt
+++ b/compiler/testData/diagnostics/testsWithJsStdLib/name/externalClassInheritance.kt
@@ -221,3 +221,34 @@ interface MyInterface {
 }
 
 class MyClass : ExternalClass(), MyInterface
+
+// FILE: InheritGenericOutExternalClass.kt
+package InheritGenericOutExternalClass
+open external class ExternalClass<out T> {
+    open fun test(x: Int?): T
+    open fun test(x: Int?, y: String?): T
+}
+
+class MyClass : ExternalClass<Unit>()
+
+// FILE: InheritGenericInExternalClass.kt
+package InheritGenericInExternalClass
+open external class ExternalClass<in T> {
+    open fun test(x: T?): Int
+    open fun test(x: T?, y: String?): Int
+}
+
+class MyClass : ExternalClass<Int>() {
+    fun test(x: Int?, y: Int?) = x ?: y ?: 1
+}
+
+// FILE: InheritGenericInExternalClassClash.kt
+package InheritGenericInExternalClassClash
+open external class ExternalClass<in T> {
+    open fun test(x: T?): Int
+    <!JS_NAME_CLASH!>open fun test(x: T?, y: String?): Int<!>
+}
+
+class MyClass : ExternalClass<Int>() {
+    <!JS_NAME_CLASH!>override fun test(x: Int?)<!> = x ?: 1
+}
diff --git a/compiler/testData/diagnostics/testsWithJsStdLib/name/externalClassInheritance.txt b/compiler/testData/diagnostics/testsWithJsStdLib/name/externalClassInheritance.txt
index 019528a3fb0..5212f703db1 100644
--- a/compiler/testData/diagnostics/testsWithJsStdLib/name/externalClassInheritance.txt
+++ b/compiler/testData/diagnostics/testsWithJsStdLib/name/externalClassInheritance.txt
@@ -17,6 +17,70 @@ package FinalExternalClass {
     }
 }
 
+package InheritGenericInExternalClass {
+
+    public open external class ExternalClass</*0*/ in T> {
+        public constructor ExternalClass</*0*/ in T>()
+        public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+        public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+        public open fun test(/*0*/ x: T?): kotlin.Int
+        public open fun test(/*0*/ x: T?, /*1*/ y: kotlin.String?): kotlin.Int
+        public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+    }
+
+    public final class MyClass : InheritGenericInExternalClass.ExternalClass<kotlin.Int> {
+        public constructor MyClass()
+        public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+        public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+        public open override /*1*/ /*fake_override*/ fun test(/*0*/ x: kotlin.Int?): kotlin.Int
+        public final fun test(/*0*/ x: kotlin.Int?, /*1*/ y: kotlin.Int?): kotlin.Int
+        public open override /*1*/ /*fake_override*/ fun test(/*0*/ x: kotlin.Int?, /*1*/ y: kotlin.String?): kotlin.Int
+        public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+    }
+}
+
+package InheritGenericInExternalClassClash {
+
+    public open external class ExternalClass</*0*/ in T> {
+        public constructor ExternalClass</*0*/ in T>()
+        public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+        public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+        public open fun test(/*0*/ x: T?): kotlin.Int
+        public open fun test(/*0*/ x: T?, /*1*/ y: kotlin.String?): kotlin.Int
+        public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+    }
+
+    public final class MyClass : InheritGenericInExternalClassClash.ExternalClass<kotlin.Int> {
+        public constructor MyClass()
+        public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+        public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+        public open override /*1*/ fun test(/*0*/ x: kotlin.Int?): kotlin.Int
+        public open override /*1*/ /*fake_override*/ fun test(/*0*/ x: kotlin.Int?, /*1*/ y: kotlin.String?): kotlin.Int
+        public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+    }
+}
+
+package InheritGenericOutExternalClass {
+
+    public open external class ExternalClass</*0*/ out T> {
+        public constructor ExternalClass</*0*/ out T>()
+        public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+        public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+        public open fun test(/*0*/ x: kotlin.Int?): T
+        public open fun test(/*0*/ x: kotlin.Int?, /*1*/ y: kotlin.String?): T
+        public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+    }
+
+    public final class MyClass : InheritGenericOutExternalClass.ExternalClass<kotlin.Unit> {
+        public constructor MyClass()
+        public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+        public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+        public open override /*1*/ /*fake_override*/ fun test(/*0*/ x: kotlin.Int?): kotlin.Unit
+        public open override /*1*/ /*fake_override*/ fun test(/*0*/ x: kotlin.Int?, /*1*/ y: kotlin.String?): kotlin.Unit
+        public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+    }
+}
+
 package OpenExternalClassWithFinalMethods {
 
     public open external class ExternalClass {
diff --git a/js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/fir/FirJsBoxTestGenerated.java b/js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/fir/FirJsBoxTestGenerated.java
index 2ce218326af..5085471fa80 100644
--- a/js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/fir/FirJsBoxTestGenerated.java
+++ b/js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/fir/FirJsBoxTestGenerated.java
@@ -8352,6 +8352,12 @@ public class FirJsBoxTestGenerated extends AbstractFirJsBoxTest {
             runTest("js/js.translator/testData/box/nameClashes/overloadMethodsWithSameParameterTypeName.kt");
         }
 
+        @Test
+        @TestMetadata("promiseThen.kt")
+        public void testPromiseThen() throws Exception {
+            runTest("js/js.translator/testData/box/nameClashes/promiseThen.kt");
+        }
+
         @Test
         @TestMetadata("propertyAndNativeMethod.kt")
         public void testPropertyAndNativeMethod() throws Exception {
diff --git a/js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/fir/FirJsES6BoxTestGenerated.java b/js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/fir/FirJsES6BoxTestGenerated.java
index 462ff3fdfd7..45e60e31a6b 100644
--- a/js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/fir/FirJsES6BoxTestGenerated.java
+++ b/js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/fir/FirJsES6BoxTestGenerated.java
@@ -8458,6 +8458,12 @@ public class FirJsES6BoxTestGenerated extends AbstractFirJsES6BoxTest {
             runTest("js/js.translator/testData/box/nameClashes/overloadMethodsWithSameParameterTypeName.kt");
         }
 
+        @Test
+        @TestMetadata("promiseThen.kt")
+        public void testPromiseThen() throws Exception {
+            runTest("js/js.translator/testData/box/nameClashes/promiseThen.kt");
+        }
+
         @Test
         @TestMetadata("propertyAndNativeMethod.kt")
         public void testPropertyAndNativeMethod() throws Exception {
diff --git a/js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/ir/IrBoxJsES6TestGenerated.java b/js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/ir/IrBoxJsES6TestGenerated.java
index fdf13861500..b7743c3a696 100644
--- a/js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/ir/IrBoxJsES6TestGenerated.java
+++ b/js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/ir/IrBoxJsES6TestGenerated.java
@@ -8458,6 +8458,12 @@ public class IrBoxJsES6TestGenerated extends AbstractIrBoxJsES6Test {
             runTest("js/js.translator/testData/box/nameClashes/overloadMethodsWithSameParameterTypeName.kt");
         }
 
+        @Test
+        @TestMetadata("promiseThen.kt")
+        public void testPromiseThen() throws Exception {
+            runTest("js/js.translator/testData/box/nameClashes/promiseThen.kt");
+        }
+
         @Test
         @TestMetadata("propertyAndNativeMethod.kt")
         public void testPropertyAndNativeMethod() throws Exception {
diff --git a/js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/ir/IrBoxJsTestGenerated.java b/js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/ir/IrBoxJsTestGenerated.java
index a1ba4965903..ae6d026ac01 100644
--- a/js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/ir/IrBoxJsTestGenerated.java
+++ b/js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/ir/IrBoxJsTestGenerated.java
@@ -8352,6 +8352,12 @@ public class IrBoxJsTestGenerated extends AbstractIrBoxJsTest {
             runTest("js/js.translator/testData/box/nameClashes/overloadMethodsWithSameParameterTypeName.kt");
         }
 
+        @Test
+        @TestMetadata("promiseThen.kt")
+        public void testPromiseThen() throws Exception {
+            runTest("js/js.translator/testData/box/nameClashes/promiseThen.kt");
+        }
+
         @Test
         @TestMetadata("propertyAndNativeMethod.kt")
         public void testPropertyAndNativeMethod() throws Exception {
diff --git a/js/js.translator/testData/box/nameClashes/promiseThen.kt b/js/js.translator/testData/box/nameClashes/promiseThen.kt
new file mode 100644
index 00000000000..81f077cdfaf
--- /dev/null
+++ b/js/js.translator/testData/box/nameClashes/promiseThen.kt
@@ -0,0 +1,6 @@
+// KJS_WITH_FULL_RUNTIME
+import kotlin.js.Promise
+
+public class MyPromise(executor: ((Unit) -> Unit, (Throwable) -> Unit) -> Unit) : Promise<Unit>(executor)
+
+fun box() = "OK"