Fix error on README page with expanded entry points

Author: Gerrit0

CHANGELOG.md

@@ -3,6 +3,7 @@
 ### Bug Fixes
 
 -   Actually fixed `@category` tag incorrectly appearing on function types if used on a type alias, #1745.
+-   Fix error in console when a page contains no documentation items.
 
 ## v0.22.7 (2021-10-25)
 

src/lib/output/themes/default/assets/typedoc/services/Viewport.ts

@@ -39,8 +39,9 @@ export class Viewport extends EventTarget {
 
     /**
      * The sticky side nav that contains members of the current page.
+     * Might not present on the home page if the project uses `entryPointStrategy` set to `Expand`.
      */
-    secondaryNav: HTMLElement;
+    secondaryNav?: HTMLElement;
 
     /**
      * Create new Viewport instance.
@@ -51,7 +52,7 @@ export class Viewport extends EventTarget {
         this.toolbar = <HTMLDivElement>(
             document.querySelector(".tsd-page-toolbar")
         );
-        this.secondaryNav = <HTMLElement>(
+        this.secondaryNav = <HTMLElement | undefined>(
             document.querySelector(".tsd-navigation.secondary")
         );
 
@@ -123,7 +124,7 @@ export class Viewport extends EventTarget {
         this.showToolbar = this.lastY >= this.scrollTop || this.scrollTop <= 0;
         if (isShown !== this.showToolbar) {
             this.toolbar.classList.toggle("tsd-page-toolbar--hide");
-            this.secondaryNav.classList.toggle("tsd-navigation--toolbar-hide");
+            this.secondaryNav?.classList.toggle("tsd-navigation--toolbar-hide");
         }
         this.lastY = this.scrollTop;
     }