diff --git a/make/jdk/src/classes/build/tools/jdwpgen/RootNode.java b/make/jdk/src/classes/build/tools/jdwpgen/RootNode.java
index 5de3ddf3518..a5eb1521f53 100644
--- a/make/jdk/src/classes/build/tools/jdwpgen/RootNode.java
+++ b/make/jdk/src/classes/build/tools/jdwpgen/RootNode.java
@@ -53,7 +53,7 @@ class RootNode extends AbstractNamedNode {
         writer.println("</head>");
         writer.println("<body>");
         writer.println("<div class=\"centered\" role=\"banner\">");
-        writer.println("<h1 id=\"Protocol Details\">Java Debug Wire Protocol Details</h1>");
+        writer.println("<h1 id=\"Protocol_Details\">Java Debug Wire Protocol Details</h1>");
         writer.println("</div>");
         writer.println("<nav>");
         writer.println("<ul>");
