diff --git a/idea/idea-analysis/src/org/jetbrains/kotlin/idea/framework/JsLibraryStdDetectionUtil.java b/idea/idea-analysis/src/org/jetbrains/kotlin/idea/framework/JsLibraryStdDetectionUtil.java
index d8f1c48a754..e54bd6b39c2 100644
--- a/idea/idea-analysis/src/org/jetbrains/kotlin/idea/framework/JsLibraryStdDetectionUtil.java
+++ b/idea/idea-analysis/src/org/jetbrains/kotlin/idea/framework/JsLibraryStdDetectionUtil.java
@@ -63,9 +63,7 @@ public class JsLibraryStdDetectionUtil {
             if (root.getFileSystem().getProtocol() != StandardFileSystems.JAR_PROTOCOL) continue;
 
             VirtualFile jar = VfsUtilCore.getVirtualFileForJar(root);
-            assert jar != null : "expected not null for root '" + root.getPath() + "'";
-
-            if (LibraryUtils.isKotlinJavascriptStdLibrary(new File(jar.getPath()))) {
+            if (jar != null && LibraryUtils.isKotlinJavascriptStdLibrary(new File(jar.getPath()))) {
                 return jar;
             }
         }