diff --git a/framework/core/js/src/common/Application.js b/framework/core/js/src/common/Application.js
index cfaac22aa..c886a423a 100644
--- a/framework/core/js/src/common/Application.js
+++ b/framework/core/js/src/common/Application.js
@@ -159,6 +159,8 @@ export default class Application {
   title = '';
   titleCount = 0;
 
+  initialRoute;
+
   load(payload) {
     this.data = payload;
     this.translator.locale = payload.locale;
@@ -174,6 +176,8 @@ export default class Application {
     this.session = new Session(this.store.getById('users', this.data.session.userId), this.data.session.csrfToken);
 
     this.mount();
+
+    this.initialRoute = window.location.href;
   }
 
   bootExtensions(extensions) {
@@ -226,7 +230,8 @@ export default class Application {
    * @public
    */
   preloadedApiDocument() {
-    if (this.data.apiDocument) {
+    // If the URL has changed, the preloaded Api document is invalid.
+    if (this.data.apiDocument && window.location.href === this.initialRoute) {
       const results = this.store.pushPayload(this.data.apiDocument);
 
       this.data.apiDocument = null;
diff --git a/framework/core/src/Forum/ForumServiceProvider.php b/framework/core/src/Forum/ForumServiceProvider.php
index 2d1915dd3..8e671dbfc 100644
--- a/framework/core/src/Forum/ForumServiceProvider.php
+++ b/framework/core/src/Forum/ForumServiceProvider.php
@@ -204,7 +204,7 @@ class ForumServiceProvider extends AbstractServiceProvider
         $factory = $this->container->make(RouteHandlerFactory::class);
         $defaultRoute = $this->container->make('flarum.settings')->get('default_route');
 
-        if (isset($routes->getRoutes()['GET'][$defaultRoute]['handler'])) {
+        if (isset($routes->getRouteData()[0]['GET'][$defaultRoute]['handler'])) {
             $toDefaultController = $routes->getRoutes()['GET'][$defaultRoute]['handler'];
         } else {
             $toDefaultController = $factory->toForum(Content\Index::class);
diff --git a/framework/core/tests/integration/forum/DefaultRouteTest.php b/framework/core/tests/integration/forum/DefaultRouteTest.php
new file mode 100644
index 000000000..892cc7498
--- /dev/null
+++ b/framework/core/tests/integration/forum/DefaultRouteTest.php
@@ -0,0 +1,99 @@
+<?php
+
+/*
+ * This file is part of Flarum.
+ *
+ * For detailed copyright and license information, please view the
+ * LICENSE file that was distributed with this source code.
+ */
+
+namespace Flarum\Tests\integration\forum;
+
+use Carbon\Carbon;
+use Flarum\Extend;
+use Flarum\Foundation\AbstractServiceProvider;
+use Flarum\Settings\SettingsRepositoryInterface;
+use Flarum\Testing\integration\TestCase;
+
+class DefaultRouteTest extends TestCase
+{
+    /**
+     * @inheritDoc
+     */
+    protected function setUp(): void
+    {
+        parent::setUp();
+
+        $this->prepareDatabase([
+            'discussions' => [
+                ['id' => 1, 'title' => 'foo bar', 'created_at' => Carbon::createFromDate(1975, 5, 21)->toDateTimeString(), 'last_posted_at' => Carbon::createFromDate(1975, 5, 21)->toDateTimeString(), 'user_id' => 1, 'first_post_id' => 1, 'comment_count' => 1],
+            ],
+            'posts' => [
+                ['id' => 1, 'discussion_id' => 1, 'created_at' => Carbon::createFromDate(1975, 5, 21)->toDateTimeString(), 'user_id' => 1, 'type' => 'comment', 'content' => '<t><p>foo bar</p></t>']
+            ]
+        ]);
+    }
+
+    /**
+     * This is necessary as we need to add the setting to the DB before the app boots.
+     */
+    protected function setDefaultRoute($defaultRoute)
+    {
+        OverrideDefaultRouteServiceProvider::$defaultRoute = $defaultRoute;
+        $this->extend(
+            (new Extend\ServiceProvider())->register(OverrideDefaultRouteServiceProvider::class)
+        );
+    }
+
+    /**
+     * @test
+     */
+    public function default_route_payload_includes_discussions()
+    {
+        $response = $this->send(
+            $this->request('GET', '/')
+        );
+
+        $this->assertStringContainsString('apiDocument', $response->getBody());
+    }
+
+    /**
+     * @test
+     */
+    public function nonexistent_custom_homepage_uses_default_payload()
+    {
+        $this->setDefaultRoute('/nonexistent');
+
+        $response = $this->send(
+            $this->request('GET', '/')
+        );
+
+        $this->assertStringContainsString('apiDocument', $response->getBody());
+    }
+
+    /**
+     * @test
+     */
+    public function existent_custom_homepage_doesnt_use_default_payload()
+    {
+        $this->setDefaultRoute('/settings');
+
+        $response = $this->send(
+            $this->request('GET', '/')
+        );
+
+        $this->assertStringNotContainsString('apiDocument', $response->getBody());
+    }
+}
+
+class OverrideDefaultRouteServiceProvider extends AbstractServiceProvider
+{
+    public static $defaultRoute;
+
+    public function register()
+    {
+        $settings = $this->container->make(SettingsRepositoryInterface::class);
+
+        $settings->set('default_route', static::$defaultRoute);
+    }
+}