diff --git a/compiler/testData/multiplatform/jsNameClash/common.kt b/compiler/testData/multiplatform/jsNameClash/common.kt
index b1c8b810b1a..fb31d05fa13 100644
--- a/compiler/testData/multiplatform/jsNameClash/common.kt
+++ b/compiler/testData/multiplatform/jsNameClash/common.kt
@@ -1,2 +1,2 @@
-header class ClassWithImplByExtension
-header val ClassWithImplByExtension.extensionVal: Int
\ No newline at end of file
+expect class ClassWithImplByExtension
+expect val ClassWithImplByExtension.extensionVal: Int
\ No newline at end of file
diff --git a/compiler/testData/multiplatform/jsNameClash/js.kt b/compiler/testData/multiplatform/jsNameClash/js.kt
index 17b3a6342f1..ffe01d01f3f 100644
--- a/compiler/testData/multiplatform/jsNameClash/js.kt
+++ b/compiler/testData/multiplatform/jsNameClash/js.kt
@@ -1,3 +1,3 @@
-impl class ClassWithImplByExtension
-impl val ClassWithImplByExtension.extensionVal: Int
+actual class ClassWithImplByExtension
+actual val ClassWithImplByExtension.extensionVal: Int
     get() = 0
\ No newline at end of file