diff --git a/.github/workflows/api-integration-tests.yml b/.github/workflows/api-integration-tests.yml
index ee2905d1d..51fa1c00f 100644
--- a/.github/workflows/api-integration-tests.yml
+++ b/.github/workflows/api-integration-tests.yml
@@ -103,7 +103,7 @@ jobs:
           database-password: ${{ env.POSTGRES_PASSWORD }}
 
       - name: Prime app build
-        run: make composer
+        run: make php-test-dependencies-appstore
 
       - name: Configure server with app
         uses: SMillerDev/nextcloud-actions/setup-nextcloud-app@b13a04eb6a4e48972d31fa07559619843fcc2102 # main
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 12f1bed81..6b9c3a4af 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,6 +10,7 @@ You can also check [on GitHub](https://github.com/nextcloud/news/releases), the
 ### Changed
 
 ### Fixed
+- Fixed News not starting since 28.5.0 due to php class loading issues (#3780)
 
 # Releases
 ## [28.5.0] - 2026-06-03
diff --git a/Makefile b/Makefile
index 7e3644b8d..20a8abc4a 100644
--- a/Makefile
+++ b/Makefile
@@ -51,9 +51,13 @@ appstore_sign_dir=$(appstore_build_directory)/sign
 cert_dir=$(HOME)/.nextcloud/certificates
 npm:=$(shell which npm 2> /dev/null)
 composer:=$(shell which composer 2> /dev/null)
+phpunit:=$(shell which phpunit 2> /dev/null)
 ifeq (,$(composer))
 	composer:=php "$(build_tools_directory)/composer.phar"
 endif
+ifeq (,$(phpunit))
+	phpunit:=./vendor/phpunit/phpunit/phpunit
+endif
 
 #Support xDebug 3.0+
 export XDEBUG_MODE=coverage
@@ -99,12 +103,12 @@ clean:
 
 # Reports PHP codestyle violations
 .PHONY: phpcs
-phpcs:
+phpcs: php-dev-dependencies-if-needed
 	./vendor/bin/phpcs --standard=PSR2 --ignore=lib/Migration/Version*.php,lib/Vendor/* lib
 
 # Reports PHP static violations
 .PHONY: phpstan
-phpstan:
+phpstan: php-dev-dependencies-if-needed
 	./vendor/bin/phpstan analyse --level=1 lib
 
 # Same as clean but also removes dependencies installed by composer and
@@ -207,6 +211,13 @@ php-test-dependencies:
 	$(composer) install --prefer-dist
 	$(composer) scope-dependencies
 
+.PHONY: php-test-dependencies-appstore
+php-test-dependencies-appstore:
+	COMPOSER_NO_PLUGINS=1 $(composer) install --prefer-dist --no-dev --no-scripts
+	COMPOSER_NO_PLUGINS=1 $(composer) scope-dependencies
+	php ./bin/tools/fix_scoped_autoload.php
+	find "vendor" -mindepth 1 -maxdepth 1 ! -name 'composer' ! -name 'autoload.php' -exec rm -rf {} +
+
 .PHONY: php-test-dependencies-if-needed
 php-test-dependencies-if-needed:
 	@if [ ! -x "./vendor/phpunit/phpunit/phpunit" ]; then \
@@ -214,6 +225,20 @@ php-test-dependencies-if-needed:
 		$(MAKE) php-test-dependencies; \
 	fi
 
+.PHONY: php-dev-dependencies-if-needed
+php-dev-dependencies-if-needed:
+	@if [ ! -x "./vendor/bin/phpstan" ]; then \
+		echo "Dev dependencies not found. Installing dev dependencies..."; \
+		$(MAKE) php-test-dependencies; \
+	fi
+
+.PHONY: php-test-dependencies-if-needed-appstore
+php-test-dependencies-if-needed-appstore:
+	@if [ ! -f "vendor/autoload.php" ] || [ ! -d "lib/Vendor" ]; then \
+		echo "Appstore-style PHP test dependencies not found. Installing scoped runtime dependencies..."; \
+		$(MAKE) php-test-dependencies-appstore; \
+	fi
+
 .PHONY: scope-if-needed
 scope-if-needed:
 	@if [ ! -d "lib/Vendor" ]; then \
@@ -225,6 +250,10 @@ scope-if-needed:
 unit-test: php-test-dependencies-if-needed scope-if-needed
 	./vendor/phpunit/phpunit/phpunit -c phpunit.xml --coverage-clover build/php-unit.clover
 
+.PHONY: unit-test-appstore
+unit-test-appstore: php-test-dependencies-if-needed-appstore scope-if-needed
+	$(phpunit) -c phpunit.xml --coverage-clover build/php-unit.clover
+
 # Command for running JS and PHP tests. Works for package.json files in the js/
 # and root directory. If phpunit is not installed systemwide, a copy is fetched
 # from the internet
diff --git a/bin/tools/fix_scoped_autoload.php b/bin/tools/fix_scoped_autoload.php
new file mode 100644
index 000000000..4934f167b
--- /dev/null
+++ b/bin/tools/fix_scoped_autoload.php
@@ -0,0 +1,95 @@
+#!/usr/bin/env php
+<?php
+
+declare(strict_types=1);
+
+$projectRoot = dirname(__DIR__, 2);
+$vendorDir = $projectRoot . '/vendor';
+$scopedDir = $projectRoot . '/lib/Vendor';
+$autoloadFilesPath = $vendorDir . '/composer/autoload_files.php';
+$autoloadStaticPath = $vendorDir . '/composer/autoload_static.php';
+
+if (!is_file($autoloadFilesPath) || !is_file($autoloadStaticPath) || !is_dir($scopedDir)) {
+    exit(0);
+}
+
+$autoloadFilesContent = file_get_contents($autoloadFilesPath);
+$autoloadStaticContent = file_get_contents($autoloadStaticPath);
+if ($autoloadFilesContent === false || $autoloadStaticContent === false) {
+    fwrite(STDERR, 'Unable to read Composer autoload files' . PHP_EOL);
+    exit(1);
+}
+
+preg_match_all('/\\$vendorDir \. \'\/([^\']+)\'/', $autoloadFilesContent, $matches);
+$fileEntries = $matches[1] ?? [];
+
+$pathMap = [];
+foreach ($fileEntries as $relativeVendorPath) {
+    $candidate = mapVendorPathToScopedPath($relativeVendorPath, $scopedDir);
+    if ($candidate === null) {
+        // Fallback: some packages have their files placed at the root of lib/Vendor
+        // (e.g. symfony/deprecation-contracts → function.php, ralouphie/getallheaders
+        // → getallheaders.php). Check for a root-level match only — never match files
+        // in subdirectories, to avoid cross-package collisions such as phpstan's
+        // bootstrap.php matching a polyfill bootstrap.php deeper in the tree.
+        $basename = basename($relativeVendorPath);
+        if (is_file($scopedDir . '/' . $basename)) {
+            $candidate = $basename;
+        }
+    }
+
+    if ($candidate === null) {
+        continue;
+    }
+
+    $pathMap[$relativeVendorPath] = $candidate;
+}
+
+if ($pathMap === []) {
+    exit(0);
+}
+
+foreach ($pathMap as $vendorRelative => $scopedRelative) {
+    $autoloadFilesContent = str_replace(
+        "\$vendorDir . '/" . $vendorRelative . "'",
+        "\$baseDir . '/lib/Vendor/" . $scopedRelative . "'",
+        $autoloadFilesContent
+    );
+    $autoloadStaticContent = str_replace(
+        "__DIR__ . '/..' . '/" . $vendorRelative . "'",
+        "__DIR__ . '/../..' . '/lib/Vendor/" . $scopedRelative . "'",
+        $autoloadStaticContent
+    );
+}
+
+if (file_put_contents($autoloadFilesPath, $autoloadFilesContent) === false
+    || file_put_contents($autoloadStaticPath, $autoloadStaticContent) === false) {
+    fwrite(STDERR, 'Unable to update Composer autoload files' . PHP_EOL);
+    exit(1);
+}
+
+function mapVendorPathToScopedPath(string $relativeVendorPath, string $scopedDir): ?string
+{
+    $parts = explode('/', $relativeVendorPath);
+    if (count($parts) < 3) {
+        return null;
+    }
+
+    $vendor = normalizePackageSegment($parts[0]);
+    $packageParts = array_map('normalizePackageSegment', explode('-', $parts[1]));
+    $tail = array_slice($parts, 2);
+
+    $candidate = $vendor . '/' . implode('/', $packageParts);
+    if ($tail !== []) {
+        $candidate .= '/' . implode('/', $tail);
+    }
+
+    return is_file($scopedDir . '/' . $candidate) ? $candidate : null;
+}
+
+function normalizePackageSegment(string $segment): string
+{
+    $words = preg_split('/[^a-zA-Z0-9]+/', $segment) ?: [];
+    $words = array_filter($words, static fn (string $word): bool => $word !== '');
+    return implode('', array_map(static fn (string $word): string => ucfirst(strtolower($word)), $words));
+}
diff --git a/composer.json b/composer.json
index 068fe417b..f893764e3 100644
--- a/composer.json
+++ b/composer.json
@@ -101,7 +101,8 @@
       "rm -Rf lib/Vendor",
       "@php lib-vendor-organizer.php build/ lib/Vendor/ \"OCA\\\\News\\\\Vendor\"",
       "rm -Rf build",
-      "composer dump-autoload"
+      "composer dump-autoload",
+      "@php bin/tools/fix_scoped_autoload.php"
     ]
   }
 }