diff --git a/CHANGELOG.md b/CHANGELOG.md
index 36a44599f..5d7732789 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -16,6 +16,7 @@ All notable changes to this project will be documented in this file.
 - AS1/2 - subtract precedence
 - AS2 - getters and setters decompilation and editing
 - AS1/2 - definefunction2 suppresssuper parameter
+- New version dialog error when no main window available
 
 ## [14.6.0] - 2021-11-22
 ### Added
diff --git a/src/com/jpexs/decompiler/flash/gui/Main.java b/src/com/jpexs/decompiler/flash/gui/Main.java
index 372ce0e82..419c13d3f 100644
--- a/src/com/jpexs/decompiler/flash/gui/Main.java
+++ b/src/com/jpexs/decompiler/flash/gui/Main.java
@@ -2523,7 +2523,7 @@ public class Main {
 
         if (!versions.isEmpty()) {
             View.execInEventDispatch(() -> {
-                NewVersionDialog newVersionDialog = new NewVersionDialog(mainFrame.getWindow(), versions);
+                NewVersionDialog newVersionDialog = new NewVersionDialog(mainFrame == null ? null :mainFrame.getWindow(), versions);
                 newVersionDialog.setVisible(true);
                 Configuration.lastUpdatesCheckDate.set(Calendar.getInstance());
             });