[6.x] Preserve Yii asset bundles registered during plugin init

CHANGELOG.md

@@ -6,6 +6,7 @@
 - Added `CraftCms\Cms\Http\Responses\CpScreenResponse::screenData()`. ([#19354](https://github.com/craftcms/cms/pull/19354))
 - Fixed a bug where cache options and tags registered via `CraftCms\Cms\Utility\Utilities\ClearCaches::add()` and `addTag()` were unavailable as Artisan commands.
 - Fixed a JavaScript error that occurred on non-Inertial pages that rendered field layout designers. ([#19380](https://github.com/craftcms/cms/discussions/19380))
+- Fixed a bug where Yii asset bundles registered with `craft\web\View::registerAssetBundle()` during plugin initialization were not included in rendered pages. ([#19393](https://github.com/craftcms/cms/pull/19393))
 - Fixed a bug where legacy asset bundle dependencies could be rendered after their dependent resources when using `craftcms/yii2-adapter`. ([#19394](https://github.com/craftcms/cms/pull/19394))
 
 ## 6.0.0-alpha.16 - 2026-08-05

yii2-adapter/src/Http/PrepareLegacyCraftApp.php

@@ -47,7 +47,6 @@ private function refreshRequestScopedComponents(Request $request): void
         $yiiRequest->csrfCookie = Craft::cookieConfig([], $yiiRequest);
 
         Craft::$app->set('request', $yiiRequest);
-        Craft::$app->set('view', Craft::createObject(App::viewConfig()));
         Craft::$app->set('user', Craft::createObject(App::userConfig()));
     }
 }

yii2-adapter/tests-laravel/Http/PrepareLegacyCraftAppTest.php

@@ -0,0 +1,28 @@
+<?php
+
+declare(strict_types=1);
+
+use CraftCms\Yii2Adapter\Http\PrepareLegacyCraftApp;
+use Illuminate\Http\Request;
+use yii\web\AssetBundle;
+
+it('preserves asset bundles registered before request middleware runs', function() {
+    Craft::$app->getView()->registerAssetBundle(InitRegisteredAsset::class);
+
+    $html = app(PrepareLegacyCraftApp::class)->handle(
+        Request::create('/'),
+        fn() => Craft::$app->getView()->placeholderHtml(),
+    );
+
+    expect($html['headHtml'])->toContain('/cms-2324.css')
+        ->and($html['bodyEndHtml'])->toContain('/cms-2324.js');
+});
+
+class InitRegisteredAsset extends AssetBundle
+{
+    public $baseUrl = '/';
+
+    public $css = ['cms-2324.css'];
+
+    public $js = ['cms-2324.js'];
+}