Improve error message for missing sync id (#14065)

Change-Id: Iab2ddc31261f198c486b9028249fab9cc2cc06a1

diff --git a/client/src/com/vaadin/client/ApplicationConnection.java b/client/src/com/vaadin/client/ApplicationConnection.java
index 694fc710609fab14d9ef9fb26d5b78986f2389a3..5d696f1ddbbe31d55cb9eb9529301550c52867a5 100644 (file)
--- a/client/src/com/vaadin/client/ApplicationConnection.java
+++ b/client/src/com/vaadin/client/ApplicationConnection.java
@@ -66,7 +66,6 @@ import com.google.gwt.user.client.Window.ClosingHandler;
 import com.google.gwt.user.client.ui.HasWidgets;
 import com.google.gwt.user.client.ui.Widget;
 import com.vaadin.client.ApplicationConfiguration.ErrorMessage;
-import com.vaadin.client.ApplicationConnection.ApplicationStoppedEvent;
 import com.vaadin.client.ResourceLoader.ResourceLoadEvent;
 import com.vaadin.client.ResourceLoader.ResourceLoadListener;
 import com.vaadin.client.communication.HasJavaScriptConnectorHelper;
@@ -1437,7 +1436,8 @@ public class ApplicationConnection implements HasHandlers {
 
             lastSeenServerSyncId = syncId;
         } else {
-            VConsole.error("Server response didn't contain an id.");
+            VConsole.error("Server response didn't contain a sync id. "
+                    + "Please verify that the server is up-to-date and that the response data has not been modified in transmission.");
         }
 
         // Handle redirect