diff --git a/jena-fuseki2/jena-fuseki-main/src/main/java/org/apache/jena/fuseki/mod/ui/FMod_UI.java b/jena-fuseki2/jena-fuseki-main/src/main/java/org/apache/jena/fuseki/mod/ui/FMod_UI.java
index ff280dc35c7..09e6cc3635f 100644
--- a/jena-fuseki2/jena-fuseki-main/src/main/java/org/apache/jena/fuseki/mod/ui/FMod_UI.java
+++ b/jena-fuseki2/jena-fuseki-main/src/main/java/org/apache/jena/fuseki/mod/ui/FMod_UI.java
@@ -64,7 +64,8 @@ public FMod_UI() {}
     private static ArgDecl argUIFiles = new ArgDecl(true, "ui");
 
     /** Java resource name used to find the UI files. */
-    private static String resourceNameUI = "webapp";
+    private static String resourceNameUI = "/webapp/index.html";
+    private static String resourceBaseNameUI = "/webapp";
     /** Directory name of the root of UI files */
     private static String directoryNameUI = "webapp";
 
@@ -153,7 +154,7 @@ private String findFusekiApp(FusekiServerCtl serverCtl) {
 
         // 3:: From a jar.
         // Format  jar:file:///.../jena-fuseki-ui-VERSION.jar!/webapp/"
-        String r = fromClasspath(resourceNameUI);
+        String r = fromClasspath(resourceNameUI, resourceBaseNameUI);
         if ( r != null ) {
             // Simplify name.
             String displayName = loggingName(r);
@@ -165,16 +166,22 @@ private String findFusekiApp(FusekiServerCtl serverCtl) {
     }
 
     // Look for "$resourceName" on the classpath.
-    private static String fromClasspath(String resourceName) {
+    private static String fromClasspath(String lookupName, String rootName) {
         // Jetty 12.0.15  => warning "Leaked mount"
         // Logger : "org.eclipse.jetty.util.resource.ResourceFactory"
         //ResourceFactory resourceFactory = ResourceFactory.root();
 
-        ResourceFactory resourceFactory = ResourceFactory.closeable();
-        Resource resource = resourceFactory.newClassLoaderResource(resourceName);
-        if ( resource != null )
-            return resource.getURI().toString();
-        return null;
+        // Jetty 12.1.9: Need to lookup the name of a resource (lookup name), not the directory (rootName)
+        try ( ResourceFactory.Closeable resourceFactory = ResourceFactory.closeable() ) {
+            Resource resource = resourceFactory.newClassLoaderResource(lookupName);
+            if ( resource == null )
+                return null;
+            String x = resource.getURI().toString();
+            int i = x.indexOf(rootName);
+            // Up to the rootName
+            x = x.substring(0, i + rootName.length());
+            return x;
+        }
     }
 
     // Look for "$path/$resourceName"
diff --git a/pom.xml b/pom.xml
index 48fbed70e26..aad4ba42287 100644
--- a/pom.xml
+++ b/pom.xml
@@ -71,7 +71,7 @@
     <ver.jakarta.json>2.0.1</ver.jakarta.json>
 
     <!-- These two must be in-step -->
-    <ver.jetty>12.1.8</ver.jetty>
+    <ver.jetty>12.1.9</ver.jetty>
     <ver.jakarta-servlet>6.1.0</ver.jakarta-servlet>
 
     <!--