feat(theming): allow to disable standalone windows

Co-authored-by: Ferdinand Thiessen <opensource@fthiessen.de>
Signed-off-by: Simon L. <szaimen@e.mail.de>

apps/theming/lib/Controller/ThemingController.php

@@ -481,7 +481,7 @@ class ThemingController extends Controller {
 						'sizes' => '16x16'
 					]
 				],
-			'display' => 'standalone'
+			'display' => $this->config->getSystemValueBool('theming.standalone_window.enabled', true) ? 'standalone' : 'browser'
 		];
 		$response = new JSONResponse($responseJS);
 		$response->cacheFor(3600);

apps/theming/tests/Controller/ThemingControllerTest.php

@@ -713,7 +713,15 @@ class ThemingControllerTest extends TestCase {
 		@$this->assertEquals($expected, $this->themingController->getImage('background'));
 	}
 
-	public function testGetManifest(): void {
+	public static function dataGetManifest(): array {
+		return [
+			[true],
+			[false],
+		];
+	}
+
+	/** @dataProvider dataGetManifest */
+	public function testGetManifest(bool $standalone): void {
 		$this->config
 			->expects($this->once())
 			->method('getAppValue')
@@ -734,6 +742,11 @@ class ThemingControllerTest extends TestCase {
 				['theming.Icon.getTouchIcon', ['app' => 'core'], 'touchicon'],
 				['theming.Icon.getFavicon', ['app' => 'core'], 'favicon'],
 			]);
+		$this->config
+			->expects($this->once())
+			->method('getSystemValueBool')
+			->with('theming.standalone_window.enabled', true)
+			->willReturn($standalone);
 		$response = new JSONResponse([
 			'name' => 'Nextcloud',
 			'start_url' => 'localhost',
@@ -750,7 +763,7 @@ class ThemingControllerTest extends TestCase {
 						'sizes' => '16x16'
 					]
 				],
-			'display' => 'standalone',
+			'display' => $standalone ? 'standalone' : 'browser',
 			'short_name' => 'Nextcloud',
 			'theme_color' => null,
 			'background_color' => null,

config/config.sample.php

@@ -2129,6 +2129,14 @@ $CONFIG = [
  */
 'enforce_theme' => '',
 
+
+/**
+ * This setting allows to disable the PWA functionality that allows browsers to open web applications in dedicated windows.
+ *
+ * Defaults to ``true``
+ */
+'theming.standalone_window.enabled' => true,
+
 /**
  * The default cipher for encrypting files. Currently supported are:
  *  - AES-256-CTR