diff --git a/compiler/testData/codegen/box/typeMapping/nothing.kt b/compiler/testData/codegen/box/typeMapping/nothing.kt
index 16a539530a2..93cafb65401 100644
--- a/compiler/testData/codegen/box/typeMapping/nothing.kt
+++ b/compiler/testData/codegen/box/typeMapping/nothing.kt
@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JS_IR
 fun box(): String {
     // kotlin.Nothing should not be loaded here
     val x = "" is Nothing
diff --git a/compiler/testData/codegen/box/typeMapping/nullableNothing.kt b/compiler/testData/codegen/box/typeMapping/nullableNothing.kt
index a9d57bdd1a5..c6a14142ab0 100644
--- a/compiler/testData/codegen/box/typeMapping/nullableNothing.kt
+++ b/compiler/testData/codegen/box/typeMapping/nullableNothing.kt
@@ -1,6 +1,13 @@
-// IGNORE_BACKEND: JS_IR
+
+var result = "fail"
+
+fun sideEffect(): Any {
+    result = "OK"
+    return Unit
+}
+
 fun box(): String {
     // This used to be problematic because of an attempt to load kotlin/Nothing class
-    val x = "" is Nothing?
-    return "OK"
+    val x = sideEffect() is Nothing?
+    return result
 }
\ No newline at end of file