diff -r 5af9fa90cd7b -r 48b88b9c11eb src/jdk.javadoc/share/classes/jdk/javadoc/internal/doclets/formats/html/AllPackagesIndexWriter.java
--- a/src/jdk.javadoc/share/classes/jdk/javadoc/internal/doclets/formats/html/AllPackagesIndexWriter.java	Wed Nov 27 12:18:40 2019 +0100
+++ b/src/jdk.javadoc/share/classes/jdk/javadoc/internal/doclets/formats/html/AllPackagesIndexWriter.java	Wed Nov 27 13:08:16 2019 +0100
@@ -26,6 +26,7 @@
 
 import javax.lang.model.element.PackageElement;
 
+import jdk.javadoc.internal.doclets.formats.html.markup.BodyContents;
 import jdk.javadoc.internal.doclets.formats.html.markup.ContentBuilder;
 import jdk.javadoc.internal.doclets.formats.html.markup.HtmlStyle;
 import jdk.javadoc.internal.doclets.formats.html.markup.HtmlTag;
@@ -46,13 +47,6 @@
 public class AllPackagesIndexWriter extends HtmlDocletWriter {
 
     /**
-     * The HTML tree for main tag.
-     */
-    protected HtmlTree mainTree = HtmlTree.MAIN();
-
-    private final Navigation navBar;
-
-    /**
      * Construct AllPackagesIndexWriter object.
      *
      * @param configuration The current configuration
@@ -60,7 +54,6 @@
      */
     public AllPackagesIndexWriter(HtmlConfiguration configuration, DocPath filename) {
         super(configuration, filename);
-        this.navBar = new Navigation(null, configuration, fixedNavDiv, PageMode.ALLPACKAGES, path);
     }
 
     /**
@@ -83,12 +76,11 @@
      */
     protected void buildAllPackagesFile() throws DocFileIOException {
         String label = resources.getText("doclet.All_Packages");
-        HtmlTree bodyTree = getBody(getWindowTitle(label));
-        HtmlTree header = HtmlTree.HEADER();
-        addTop(header);
+        Content headerContent = new ContentBuilder();
+        Navigation navBar = new Navigation(null, configuration, PageMode.ALLPACKAGES, path);
+        addTop(headerContent);
         navBar.setUserHeader(getUserHeaderFooter(true));
-        header.add(navBar.getContent(true));
-        bodyTree.add(header);
+        headerContent.add(navBar.getContent(true));
         HtmlTree div = new HtmlTree(HtmlTag.DIV);
         div.setStyle(HtmlStyle.allPackagesContainer);
         addPackages(div);
@@ -96,14 +88,17 @@
         Content pHeading = HtmlTree.HEADING(Headings.PAGE_TITLE_HEADING, true,
                 HtmlStyle.title, titleContent);
         Content headerDiv = HtmlTree.DIV(HtmlStyle.header, pHeading);
-        mainTree.add(headerDiv);
-        mainTree.add(div);
-        bodyTree.add(mainTree);
         Content footer = HtmlTree.FOOTER();
         navBar.setUserFooter(getUserHeaderFooter(false));
         footer.add(navBar.getContent(false));
         addBottom(footer);
-        bodyTree.add(footer);
+        HtmlTree bodyTree = getBody(getWindowTitle(label));
+        bodyTree.add(new BodyContents()
+                .setHeader(headerContent)
+                .addMainContent(headerDiv)
+                .addMainContent(div)
+                .setFooter(footer)
+                .toContent());
         printHtmlDocument(null, "package index", bodyTree);
     }