diff --git a/platform/core-impl/src/com/intellij/psi/impl/ElementBase.java b/platform/core-impl/src/com/intellij/psi/impl/ElementBase.java
index 5c4d37cf363a..f79da01abbc7 100644
--- a/platform/core-impl/src/com/intellij/psi/impl/ElementBase.java
+++ b/platform/core-impl/src/com/intellij/psi/impl/ElementBase.java
@@ -3,6 +3,7 @@ package com.intellij.psi.impl;
 
 import com.intellij.ide.FileIconUtil;
 import com.intellij.navigation.ItemPresentation;
+import com.intellij.openapi.application.ApplicationManager;
 import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.openapi.fileTypes.FileType;
 import com.intellij.openapi.fileTypes.INativeFileType;
@@ -74,7 +75,7 @@ public abstract class ElementBase extends UserDataHolderBase implements Iconable
     PsiElement psiElement = (PsiElement)this;
     if (!psiElement.isValid()) return null;
 
-    if (Registry.is("psi.deferIconLoading", true)) {
+    if (shouldDeferIcon()) {
       Icon baseIcon = LastComputedIconCache.get(psiElement, flags);
       if (baseIcon == null) {
         baseIcon = AstLoadingFilter.disallowTreeLoading(() -> computeBaseIcon(flags));
@@ -89,6 +90,14 @@ public abstract class ElementBase extends UserDataHolderBase implements Iconable
     return computeIconNow(psiElement, flags);
   }
 
+  private static boolean shouldDeferIcon() {
+    if (!Registry.is("psi.deferIconLoading", true)) return false;
+    if (EDT.isCurrentThreadEdt()) return true;
+    // Unit tests often don't create actual UI, so the deferred icon is never resolved.
+    // Sometimes this causes tests to fail in really unpredictable ways.
+    return !ApplicationManager.getApplication().isUnitTestMode();
+  }
+
   private static @Nullable Icon computeIconNow(@NotNull PsiElement element, @Iconable.IconFlags int flags) {
     return AstLoadingFilter.disallowTreeLoading(() -> doComputeIconNow(element, flags));
   }