diff --git a/plugins/junit/src/com/intellij/execution/junit/JUnit3Framework.java b/plugins/junit/src/com/intellij/execution/junit/JUnit3Framework.java
index 0a0a34e6cc1e..38ad0149cf1e 100644
--- a/plugins/junit/src/com/intellij/execution/junit/JUnit3Framework.java
+++ b/plugins/junit/src/com/intellij/execution/junit/JUnit3Framework.java
@@ -13,6 +13,8 @@ public class JUnit3Framework extends JUnitTestFramework {
 
   @Override
   public boolean isDumbAware() {
+    // Only Java is available in dumb mode, other language implementation might not support it.
+    // For example, Kotlin, because it relies on light classes which require resolve.
     return this.getClass().isAssignableFrom(JUnit3Framework.class);
   }
 
diff --git a/plugins/junit/src/com/intellij/execution/junit/JUnit4Framework.java b/plugins/junit/src/com/intellij/execution/junit/JUnit4Framework.java
index 91a08bb23f1f..1c7084c5c701 100644
--- a/plugins/junit/src/com/intellij/execution/junit/JUnit4Framework.java
+++ b/plugins/junit/src/com/intellij/execution/junit/JUnit4Framework.java
@@ -18,6 +18,8 @@ public class JUnit4Framework extends JUnitTestFramework {
 
   @Override
   public boolean isDumbAware() {
+    // Only Java is available in dumb mode, other language implementation might not support it.
+    // For example, Kotlin, because it relies on light classes which require resolve.
     return this.getClass().isAssignableFrom(JUnit4Framework.class);
   }
 
diff --git a/plugins/junit/src/com/intellij/execution/junit/JUnit5Framework.java b/plugins/junit/src/com/intellij/execution/junit/JUnit5Framework.java
index 57657e027a7f..ab4222593c9f 100644
--- a/plugins/junit/src/com/intellij/execution/junit/JUnit5Framework.java
+++ b/plugins/junit/src/com/intellij/execution/junit/JUnit5Framework.java
@@ -25,6 +25,8 @@ public class JUnit5Framework extends JUnitTestFramework {
 
   @Override
   public boolean isDumbAware() {
+    // Only Java is available in dumb mode, other language implementation might not support it.
+    // For example, Kotlin, because it relies on light classes which require resolve.
     return this.getClass().isAssignableFrom(JUnit5Framework.class);
   }
 
diff --git a/plugins/junit/src/com/intellij/execution/junit/JUnit6Framework.java b/plugins/junit/src/com/intellij/execution/junit/JUnit6Framework.java
index 768112bd8bee..f5fe92590c57 100644
--- a/plugins/junit/src/com/intellij/execution/junit/JUnit6Framework.java
+++ b/plugins/junit/src/com/intellij/execution/junit/JUnit6Framework.java
@@ -13,6 +13,8 @@ import static com.siyeh.ig.junit.JUnitCommonClassNames.ORG_JUNIT_JUPITER_API_MET
 public class JUnit6Framework extends JUnit5Framework {
   @Override
   public boolean isDumbAware() {
+    // Only Java is available in dumb mode, other language implementation might not support it.
+    // For example, Kotlin, because it relies on light classes which require resolve.
     return this.getClass().isAssignableFrom(JUnit6Framework.class);
   }