diff --git a/kotlinx-coroutines-core/api/kotlinx-coroutines-core.klib.api b/kotlinx-coroutines-core/api/kotlinx-coroutines-core.klib.api
index a820fe0b35..5d45fb6e26 100644
--- a/kotlinx-coroutines-core/api/kotlinx-coroutines-core.klib.api
+++ b/kotlinx-coroutines-core/api/kotlinx-coroutines-core.klib.api
@@ -944,11 +944,6 @@ final suspend fun (org.w3c.dom/Window).kotlinx.coroutines/awaitAnimationFrame():
 // Targets: [js]
 final suspend fun <#A: kotlin/Any?> (kotlin.js/Promise<#A>).kotlinx.coroutines/await(): #A // kotlinx.coroutines/await|await@kotlin.js.Promise<0:0>(){0§<kotlin.Any?>}[0]
 // Targets: [wasmJs]
-abstract class kotlinx.coroutines/W3CWindow { // kotlinx.coroutines/W3CWindow|null[0]
-    constructor <init>() // kotlinx.coroutines/W3CWindow.<init>|<init>(){}[0]
-    final fun clearTimeout(kotlin/Int) // kotlinx.coroutines/W3CWindow.clearTimeout|clearTimeout(kotlin.Int){}[0]
-}
-// Targets: [wasmJs]
 final fun <#A: kotlin/Any?> (kotlin.js/Promise<kotlin.js/JsAny?>).kotlinx.coroutines/asDeferred(): kotlinx.coroutines/Deferred<#A> // kotlinx.coroutines/asDeferred|asDeferred@kotlin.js.Promise<kotlin.js.JsAny?>(){0§<kotlin.Any?>}[0]
 // Targets: [wasmJs]
 final fun <#A: kotlin/Any?> (kotlinx.coroutines/CoroutineScope).kotlinx.coroutines/promise(kotlin.coroutines/CoroutineContext = ..., kotlinx.coroutines/CoroutineStart = ..., kotlin.coroutines/SuspendFunction1<kotlinx.coroutines/CoroutineScope, #A>): kotlin.js/Promise<kotlin.js/JsAny?> // kotlinx.coroutines/promise|promise@kotlinx.coroutines.CoroutineScope(kotlin.coroutines.CoroutineContext;kotlinx.coroutines.CoroutineStart;kotlin.coroutines.SuspendFunction1<kotlinx.coroutines.CoroutineScope,0:0>){0§<kotlin.Any?>}[0]
diff --git a/kotlinx-coroutines-core/js/src/JSDispatcher.kt b/kotlinx-coroutines-core/js/src/JSDispatcher.kt
index f547c154b0..f0cd50a0b8 100644
--- a/kotlinx-coroutines-core/js/src/JSDispatcher.kt
+++ b/kotlinx-coroutines-core/js/src/JSDispatcher.kt
@@ -3,7 +3,7 @@ package kotlinx.coroutines
 import org.w3c.dom.*
 import kotlin.js.Promise
 
-public actual typealias W3CWindow = Window
+internal actual typealias W3CWindow = Window
 
 internal actual fun w3cSetTimeout(window: W3CWindow, handler: () -> Unit, timeout: Int): Int =
     setTimeout(window, handler, timeout)
diff --git a/kotlinx-coroutines-core/jsAndWasmJsShared/src/internal/JSDispatcher.kt b/kotlinx-coroutines-core/jsAndWasmJsShared/src/internal/JSDispatcher.kt
index eee75ffc50..c98a0672c9 100644
--- a/kotlinx-coroutines-core/jsAndWasmJsShared/src/internal/JSDispatcher.kt
+++ b/kotlinx-coroutines-core/jsAndWasmJsShared/src/internal/JSDispatcher.kt
@@ -3,7 +3,7 @@ package kotlinx.coroutines
 import kotlinx.coroutines.internal.*
 import kotlin.coroutines.*
 
-public expect abstract class W3CWindow
+internal expect abstract class W3CWindow
 internal expect fun w3cSetTimeout(window: W3CWindow, handler: () -> Unit, timeout: Int): Int
 internal expect fun w3cSetTimeout(handler: () -> Unit, timeout: Int): Int
 internal expect fun w3cClearTimeout(handle: Int)
diff --git a/kotlinx-coroutines-core/wasmJs/src/JSDispatcher.kt b/kotlinx-coroutines-core/wasmJs/src/JSDispatcher.kt
index e33841e4fe..d5a95190c5 100644
--- a/kotlinx-coroutines-core/wasmJs/src/JSDispatcher.kt
+++ b/kotlinx-coroutines-core/wasmJs/src/JSDispatcher.kt
@@ -2,7 +2,7 @@ package kotlinx.coroutines
 
 import kotlin.js.*
 
-public actual abstract external class W3CWindow {
+internal actual abstract external class W3CWindow {
     fun clearTimeout(handle: Int)
 }