diff --git a/apps/settings/templates/help.php b/apps/settings/templates/help.php
index 1488399679122..17356e6ccdf8a 100644
--- a/apps/settings/templates/help.php
+++ b/apps/settings/templates/help.php
@@ -3,7 +3,7 @@
  * SPDX-FileCopyrightText: 2019 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
  */
-\OC_Util::addStyle('settings', 'help');
+\OCP\Util::addStyle('settings', 'help');
 ?>
 <?php if ($_['knowledgebaseEmbedded'] === true) : ?>
 	<div id="app-navigation" role="navigation" tabindex="0">
diff --git a/build/psalm-baseline.xml b/build/psalm-baseline.xml
index 1a94fd88a17f5..a8db3332dc98e 100644
--- a/build/psalm-baseline.xml
+++ b/build/psalm-baseline.xml
@@ -2607,11 +2607,6 @@
       <code><![CDATA[\Test\Util\User\Dummy]]></code>
     </UndefinedClass>
   </file>
-  <file src="lib/private/legacy/OC_Util.php">
-    <InvalidReturnType>
-      <code><![CDATA[void]]></code>
-    </InvalidReturnType>
-  </file>
   <file src="lib/public/AppFramework/ApiController.php">
     <NoInterfaceProperties>
       <code><![CDATA[$this->request->server]]></code>
diff --git a/core/Listener/BeforeTemplateRenderedListener.php b/core/Listener/BeforeTemplateRenderedListener.php
index 4ce892664e9c2..cc1dee91cfe8b 100644
--- a/core/Listener/BeforeTemplateRenderedListener.php
+++ b/core/Listener/BeforeTemplateRenderedListener.php
@@ -37,7 +37,7 @@ public function handle(Event $event): void {
 			Util::addScript('core', 'public');
 		}
 
-		\OC_Util::addStyle('server', null, true);
+		Util::addStyle('server', null, true);
 
 		if ($event instanceof BeforeLoginTemplateRenderedEvent) {
 			// todo: make login work without these
diff --git a/core/js/tests/specs/coreSpec.js b/core/js/tests/specs/coreSpec.js
index a36d8320227e6..195b6dca99ac6 100644
--- a/core/js/tests/specs/coreSpec.js
+++ b/core/js/tests/specs/coreSpec.js
@@ -359,7 +359,7 @@ describe('Core base tests', function() {
 		// to make sure they run.
 		var cit = window.isPhantom?xit:it;
 
-		// must provide the same results as \OC_Util::naturalSortCompare
+		// must provide the same results as \OCP\Util::naturalSortCompare
 		it('sorts alphabetically', function() {
 			var a = [
 				'def',
diff --git a/cypress/e2e/settings/users.cy.ts b/cypress/e2e/settings/users.cy.ts
index 417191b26f864..5b8726e92ca34 100644
--- a/cypress/e2e/settings/users.cy.ts
+++ b/cypress/e2e/settings/users.cy.ts
@@ -115,12 +115,13 @@ describe('Settings: Create and delete accounts', function() {
 
 			// The "Delete account" action in the actions menu is shown and clicked
 			cy.get('.action-item__popper .action').contains('Delete account').should('exist').click({ force: true })
-			// And confirmation dialog accepted
-			cy.get('.nc-generic-dialog button').contains(`Delete ${testUser.userId}`).click({ force: true })
 
 			// Make sure no confirmation modal is shown
 			handlePasswordConfirmation(admin.password)
 
+			// And confirmation dialog accepted
+			cy.get('.nc-generic-dialog button').contains(`Delete ${testUser.userId}`).click({ force: true })
+
 			// deleted clicked the user is not shown anymore
 			getUserListRow(testUser.userId).should('not.exist')
 		})
diff --git a/lib/base.php b/lib/base.php
index bda6b6e01a1a5..c1182e47d6120 100644
--- a/lib/base.php
+++ b/lib/base.php
@@ -704,7 +704,7 @@ public static function init(): void {
 			if (count($errors) > 0) {
 				if (!self::$CLI) {
 					http_response_code(503);
-					OC_Util::addStyle('guest');
+					Util::addStyle('guest');
 					try {
 						Server::get(ITemplateManager::class)->printGuestPage('', 'error', ['errors' => $errors]);
 						exit;
diff --git a/lib/private/Image.php b/lib/private/Image.php
index 3dd0bc4966211..96699a0046b2b 100644
--- a/lib/private/Image.php
+++ b/lib/private/Image.php
@@ -56,7 +56,7 @@ public function __construct(
 		$this->appConfig = $appConfig ?? Server::get(IAppConfig::class);
 		$this->config = $config ?? Server::get(IConfig::class);
 
-		if (\OC_Util::fileInfoLoaded()) {
+		if (class_exists(finfo::class)) {
 			$this->fileInfo = new finfo(FILEINFO_MIME_TYPE);
 		}
 	}
diff --git a/lib/private/Setup.php b/lib/private/Setup.php
index f2b8a4c66a2c4..6d3021aff713d 100644
--- a/lib/private/Setup.php
+++ b/lib/private/Setup.php
@@ -21,12 +21,14 @@
 use OCP\AppFramework\Utility\ITimeFactory;
 use OCP\BackgroundJob\IJobList;
 use OCP\Defaults;
+use OCP\Http\Client\IClientService;
 use OCP\IAppConfig;
 use OCP\IConfig;
 use OCP\IGroup;
 use OCP\IGroupManager;
 use OCP\IL10N;
 use OCP\IRequest;
+use OCP\IURLGenerator;
 use OCP\IUserManager;
 use OCP\IUserSession;
 use OCP\L10N\IFactory as IL10NFactory;
@@ -170,8 +172,7 @@ public function getSystemInfo(bool $allowAllDatabases = false): array {
 			self::protectDataDirectory();
 
 			try {
-				$util = new \OC_Util();
-				$htAccessWorking = $util->isHtaccessWorking(Server::get(IConfig::class));
+				$htAccessWorking = $this->isHtaccessWorking($dataDir);
 			} catch (\OCP\HintException $e) {
 				$errors[] = [
 					'error' => $e->getMessage(),
@@ -212,6 +213,87 @@ public function getSystemInfo(bool $allowAllDatabases = false): array {
 		];
 	}
 
+	public function createHtaccessTestFile(string $dataDir): string|false {
+		// php dev server does not support htaccess
+		if (php_sapi_name() === 'cli-server') {
+			return false;
+		}
+
+		// testdata
+		$fileName = '/htaccesstest.txt';
+		$testContent = 'This is used for testing whether htaccess is properly enabled to disallow access from the outside. This file can be safely removed.';
+
+		// creating a test file
+		$testFile = $dataDir . '/' . $fileName;
+
+		if (file_exists($testFile)) {// already running this test, possible recursive call
+			return false;
+		}
+
+		$fp = @fopen($testFile, 'w');
+		if (!$fp) {
+			throw new \OCP\HintException('Can\'t create test file to check for working .htaccess file.',
+				'Make sure it is possible for the web server to write to ' . $testFile);
+		}
+		fwrite($fp, $testContent);
+		fclose($fp);
+
+		return $testContent;
+	}
+
+	/**
+	 * Check if the .htaccess file is working
+	 *
+	 * @param \OCP\IConfig $config
+	 * @return bool
+	 * @throws Exception
+	 * @throws \OCP\HintException If the test file can't get written.
+	 */
+	public function isHtaccessWorking(string $dataDir) {
+		$config = Server::get(IConfig::class);
+
+		if (\OC::$CLI || !$config->getSystemValueBool('check_for_working_htaccess', true)) {
+			return true;
+		}
+
+		$testContent = $this->createHtaccessTestFile($dataDir);
+		if ($testContent === false) {
+			return false;
+		}
+
+		$fileName = '/htaccesstest.txt';
+		$testFile = $dataDir . '/' . $fileName;
+
+		// accessing the file via http
+		$url = Server::get(IURLGenerator::class)->getAbsoluteURL(\OC::$WEBROOT . '/data' . $fileName);
+		try {
+			$content = Server::get(IClientService::class)->newClient()->get($url)->getBody();
+		} catch (\Exception $e) {
+			$content = false;
+		}
+
+		if (str_starts_with($url, 'https:')) {
+			$url = 'http:' . substr($url, 6);
+		} else {
+			$url = 'https:' . substr($url, 5);
+		}
+
+		try {
+			$fallbackContent = Server::get(IClientService::class)->newClient()->get($url)->getBody();
+		} catch (\Exception $e) {
+			$fallbackContent = false;
+		}
+
+		// cleanup
+		@unlink($testFile);
+
+		/*
+		 * If the content is not equal to test content our .htaccess
+		 * is working as required
+		 */
+		return $content !== $testContent && $fallbackContent !== $testContent;
+	}
+
 	/**
 	 * @return array<string|array> errors
 	 */
diff --git a/lib/private/Share20/Manager.php b/lib/private/Share20/Manager.php
index 1749783bc51a5..b8257d317984d 100644
--- a/lib/private/Share20/Manager.php
+++ b/lib/private/Share20/Manager.php
@@ -1965,14 +1965,9 @@ public function currentUserCanEnumerateTargetUser(?IUser $currentUser, IUser $ta
 	}
 
 	/**
-	 * Copied from \OC_Util::isSharingDisabledForUser
-	 *
-	 * TODO: Deprecate function from OC_Util
-	 *
-	 * @param string $userId
-	 * @return bool
+	 * Check if sharing is disabled for the current user
 	 */
-	public function sharingDisabledForUser($userId) {
+	public function sharingDisabledForUser(?string $userId): bool {
 		return $this->shareDisableChecker->sharingDisabledForUser($userId);
 	}
 
diff --git a/lib/private/Share20/ShareDisableChecker.php b/lib/private/Share20/ShareDisableChecker.php
index 9b8bc01558c59..8cf523b8b31c1 100644
--- a/lib/private/Share20/ShareDisableChecker.php
+++ b/lib/private/Share20/ShareDisableChecker.php
@@ -25,12 +25,7 @@ public function __construct(
 		$this->sharingDisabledForUsersCache = new CappedMemoryCache();
 	}
 
-
-	/**
-	 * @param ?string $userId
-	 * @return bool
-	 */
-	public function sharingDisabledForUser(?string $userId) {
+	public function sharingDisabledForUser(?string $userId): bool {
 		if ($userId === null) {
 			return false;
 		}
diff --git a/lib/private/Template/JSConfigHelper.php b/lib/private/Template/JSConfigHelper.php
index 5743d2965d2c4..93f5d7a5866ac 100644
--- a/lib/private/Template/JSConfigHelper.php
+++ b/lib/private/Template/JSConfigHelper.php
@@ -30,6 +30,7 @@
 use OCP\ISession;
 use OCP\IURLGenerator;
 use OCP\IUser;
+use OCP\Server;
 use OCP\ServerVersion;
 use OCP\Session\Exceptions\SessionNotAvailableException;
 use OCP\Share\IManager as IShareManager;
@@ -161,6 +162,8 @@ public function getConfig(): string {
 			'enable_non-accessible_features' => $this->config->getSystemValueBool('enable_non-accessible_features', true),
 		];
 
+		$shareManager = Server::get(IShareManager::class);
+
 		$array = [
 			'_oc_debug' => $this->config->getSystemValue('debug', false) ? 'true' : 'false',
 			'_oc_isadmin' => $uid !== null && $this->groupManager->isAdmin($uid) ? 'true' : 'false',
@@ -235,11 +238,11 @@ public function getConfig(): string {
 					'defaultExpireDateEnforced' => $enforceDefaultExpireDate,
 					'enforcePasswordForPublicLink' => Util::isPublicLinkPasswordRequired(),
 					'enableLinkPasswordByDefault' => $enableLinkPasswordByDefault,
-					'sharingDisabledForUser' => Util::isSharingDisabledForUser(),
+					'sharingDisabledForUser' => $shareManager->sharingDisabledForUser($uid),
 					'resharingAllowed' => Share::isResharingAllowed(),
 					'remoteShareAllowed' => $outgoingServer2serverShareEnabled,
 					'federatedCloudShareDoc' => $this->urlGenerator->linkToDocs('user-sharing-federated'),
-					'allowGroupSharing' => \OC::$server->get(IShareManager::class)->allowGroupSharing(),
+					'allowGroupSharing' => $shareManager->allowGroupSharing(),
 					'defaultInternalExpireDateEnabled' => $defaultInternalExpireDateEnabled,
 					'defaultInternalExpireDate' => $defaultInternalExpireDate,
 					'defaultInternalExpireDateEnforced' => $defaultInternalExpireDateEnforced,
diff --git a/lib/private/Template/functions.php b/lib/private/Template/functions.php
index 77a1e831008c5..402a7491e035d 100644
--- a/lib/private/Template/functions.php
+++ b/lib/private/Template/functions.php
@@ -131,10 +131,10 @@ function script($app, $file = null): void {
 function style($app, $file = null): void {
 	if (is_array($file)) {
 		foreach ($file as $f) {
-			OC_Util::addStyle($app, $f);
+			Util::addStyle($app, $f);
 		}
 	} else {
-		OC_Util::addStyle($app, $file);
+		Util::addStyle($app, $file);
 	}
 }
 
@@ -143,6 +143,7 @@ function style($app, $file = null): void {
  * @param string $app the appname
  * @param string|string[] $file the filename,
  *                              if an array is given it will add all styles
+ * @deprecated 32.0.0
  */
 function vendor_style($app, $file = null): void {
 	if (is_array($file)) {
diff --git a/lib/private/legacy/OC_Util.php b/lib/private/legacy/OC_Util.php
index b2950275e41c0..580fec7b5b3e2 100644
--- a/lib/private/legacy/OC_Util.php
+++ b/lib/private/legacy/OC_Util.php
@@ -9,7 +9,6 @@
 use OC\Authentication\TwoFactorAuth\Manager as TwoFactorAuthManager;
 use OC\Files\SetupManager;
 use OCP\Files\Template\ITemplateManager;
-use OCP\Http\Client\IClientService;
 use OCP\IConfig;
 use OCP\IGroupManager;
 use OCP\IURLGenerator;
@@ -19,17 +18,13 @@
 use OCP\Share\IManager;
 use Psr\Log\LoggerInterface;
 
+/**
+ * @deprecated 32.0.0 Use \OCP\Util or any appropriate official API instead
+ */
 class OC_Util {
 	public static $styles = [];
 	public static $headers = [];
 
-	/** @var array Local cache of version.php */
-	private static $versionCache = null;
-
-	protected static function getAppManager() {
-		return \OC::$server->getAppManager();
-	}
-
 	/**
 	 * Setup the file system
 	 *
@@ -62,8 +57,8 @@ public static function setupFS(?string $user = '') {
 	 * Check if a password is required for each public link
 	 *
 	 * @param bool $checkGroupMembership Check group membership exclusion
-	 * @return boolean
-	 * @suppress PhanDeprecatedFunction
+	 * @return bool
+	 * @deprecated 32.0.0 use OCP\Share\IManager's shareApiLinkEnforcePassword directly
 	 */
 	public static function isPublicLinkPasswordRequired(bool $checkGroupMembership = true) {
 		/** @var IManager $shareManager */
@@ -77,6 +72,7 @@ public static function isPublicLinkPasswordRequired(bool $checkGroupMembership =
 	 * @param IGroupManager $groupManager
 	 * @param IUser|null $user
 	 * @return bool
+	 * @deprecated 32.0.0 use OCP\Share\IManager's sharingDisabledForUser directly
 	 */
 	public static function isSharingDisabledForUser(IConfig $config, IGroupManager $groupManager, $user) {
 		/** @var IManager $shareManager */
@@ -89,7 +85,7 @@ public static function isSharingDisabledForUser(IConfig $config, IGroupManager $
 	 * check if share API enforces a default expire date
 	 *
 	 * @return bool
-	 * @suppress PhanDeprecatedFunction
+	 * @deprecated 32.0.0 use OCP\Share\IManager's shareApiLinkDefaultExpireDateEnforced directly
 	 */
 	public static function isDefaultExpireDateEnforced() {
 		/** @var IManager $shareManager */
@@ -205,12 +201,10 @@ public static function copyr($source, \OCP\Files\Folder $target) {
 	}
 
 	/**
-	 * @return void
-	 * @suppress PhanUndeclaredMethod
+	 * @deprecated 32.0.0 Call tearDown directly on SetupManager
 	 */
-	public static function tearDownFS() {
-		/** @var SetupManager $setupManager */
-		$setupManager = \OC::$server->get(SetupManager::class);
+	public static function tearDownFS(): void {
+		$setupManager = \OCP\Server::get(SetupManager::class);
 		$setupManager->tearDown();
 	}
 
@@ -219,10 +213,9 @@ public static function tearDownFS() {
 	 *
 	 * @param string $application application to get the files from
 	 * @param string $directory directory within this application (css, js, vendor, etc)
-	 * @param string $file the file inside of the above folder
-	 * @return string the path
+	 * @param ?string $file the file inside of the above folder
 	 */
-	private static function generatePath($application, $directory, $file) {
+	private static function generatePath($application, $directory, $file): string {
 		if (is_null($file)) {
 			$file = $application;
 			$application = '';
@@ -240,9 +233,9 @@ private static function generatePath($application, $directory, $file) {
 	 * @param string $application application id
 	 * @param string|null $file filename
 	 * @param bool $prepend prepend the Style to the beginning of the list
-	 * @return void
+	 * @deprecated 32.0.0 Use \OCP\Util::addStyle
 	 */
-	public static function addStyle($application, $file = null, $prepend = false) {
+	public static function addStyle($application, $file = null, $prepend = false): void {
 		$path = OC_Util::generatePath($application, 'css', $file);
 		self::addExternalResource($application, $prepend, $path, 'style');
 	}
@@ -253,9 +246,9 @@ public static function addStyle($application, $file = null, $prepend = false) {
 	 * @param string $application application id
 	 * @param string|null $file filename
 	 * @param bool $prepend prepend the Style to the beginning of the list
-	 * @return void
+	 * @deprecated 32.0.0
 	 */
-	public static function addVendorStyle($application, $file = null, $prepend = false) {
+	public static function addVendorStyle($application, $file = null, $prepend = false): void {
 		$path = OC_Util::generatePath($application, 'vendor', $file);
 		self::addExternalResource($application, $prepend, $path, 'style');
 	}
@@ -267,9 +260,8 @@ public static function addVendorStyle($application, $file = null, $prepend = fal
 	 * @param bool $prepend prepend the file to the beginning of the list
 	 * @param string $path
 	 * @param string $type (script or style)
-	 * @return void
 	 */
-	private static function addExternalResource($application, $prepend, $path, $type = 'script') {
+	private static function addExternalResource($application, $prepend, $path, $type = 'script'): void {
 		if ($type === 'style') {
 			if (!in_array($path, self::$styles)) {
 				if ($prepend === true) {
@@ -289,8 +281,9 @@ private static function addExternalResource($application, $prepend, $path, $type
 	 * @param array $attributes array of attributes for the element
 	 * @param string $text the text content for the element
 	 * @param bool $prepend prepend the header to the beginning of the list
+	 * @deprecated 32.0.0 Use \OCP\Util::addHeader instead
 	 */
-	public static function addHeader($tag, $attributes, $text = null, $prepend = false) {
+	public static function addHeader($tag, $attributes, $text = null, $prepend = false): void {
 		$header = [
 			'tag' => $tag,
 			'attributes' => $attributes,
@@ -306,7 +299,6 @@ public static function addHeader($tag, $attributes, $text = null, $prepend = fal
 	/**
 	 * check if the current server configuration is suitable for ownCloud
 	 *
-	 * @param \OC\SystemConfig $config
 	 * @return array arrays with error messages and hints
 	 */
 	public static function checkServer(\OC\SystemConfig $config) {
@@ -529,6 +521,7 @@ public static function checkServer(\OC\SystemConfig $config) {
 	 *
 	 * @param string $dataDirectory
 	 * @return array arrays with error messages and hints
+	 * @internal
 	 */
 	public static function checkDataDirectoryPermissions($dataDirectory) {
 		if (!\OC::$server->getConfig()->getSystemValueBool('check_data_directory_permissions', true)) {
@@ -557,6 +550,7 @@ public static function checkDataDirectoryPermissions($dataDirectory) {
 	 *
 	 * @param string $dataDirectory data directory path
 	 * @return array errors found
+	 * @internal
 	 */
 	public static function checkDataDirectoryValidity($dataDirectory) {
 		$l = \OC::$server->getL10N('lib');
@@ -581,9 +575,9 @@ public static function checkDataDirectoryValidity($dataDirectory) {
 	 * Check if the user is logged in, redirects to home if not. With
 	 * redirect URL parameter to the request URI.
 	 *
-	 * @return void
+	 * @deprecated 32.0.0
 	 */
-	public static function checkLoggedIn() {
+	public static function checkLoggedIn(): void {
 		// Check if we are a user
 		if (!\OC::$server->getUserSession()->isLoggedIn()) {
 			header('Location: ' . \OC::$server->getURLGenerator()->linkToRoute(
@@ -605,10 +599,10 @@ public static function checkLoggedIn() {
 	/**
 	 * Check if the user is a admin, redirects to home if not
 	 *
-	 * @return void
+	 * @deprecated 32.0.0
 	 */
-	public static function checkAdminUser() {
-		OC_Util::checkLoggedIn();
+	public static function checkAdminUser(): void {
+		self::checkLoggedIn();
 		if (!OC_User::isAdminUser(OC_User::getUser())) {
 			header('Location: ' . \OCP\Util::linkToAbsolute('', 'index.php'));
 			exit();
@@ -621,7 +615,7 @@ public static function checkAdminUser() {
 	 * the apps visible for the current user
 	 *
 	 * @return string URL
-	 * @suppress PhanDeprecatedFunction
+	 * @deprecated 32.0.0 use IURLGenerator's linkToDefaultPageUrl directly
 	 */
 	public static function getDefaultPageUrl() {
 		/** @var IURLGenerator $urlGenerator */
@@ -632,9 +626,9 @@ public static function getDefaultPageUrl() {
 	/**
 	 * Redirect to the user default page
 	 *
-	 * @return void
+	 * @deprecated 32.0.0
 	 */
-	public static function redirectToDefaultPage() {
+	public static function redirectToDefaultPage(): void {
 		$location = self::getDefaultPageUrl();
 		header('Location: ' . $location);
 		exit();
@@ -645,7 +639,7 @@ public static function redirectToDefaultPage() {
 	 *
 	 * @return string
 	 */
-	public static function getInstanceId() {
+	public static function getInstanceId(): string {
 		$id = \OC::$server->getSystemConfig()->getValue('instanceid', null);
 		if (is_null($id)) {
 			// We need to guarantee at least one letter in instanceid so it can be used as the session_name
@@ -663,6 +657,7 @@ public static function getInstanceId() {
 	 *
 	 * @param string|string[] $value
 	 * @return ($value is array ? string[] : string)
+	 * @deprecated 32.0.0 use \OCP\Util::sanitizeHTML instead
 	 */
 	public static function sanitizeHTML($value) {
 		if (is_array($value)) {
@@ -685,6 +680,7 @@ public static function sanitizeHTML($value) {
 	 *
 	 * @param string $component part of URI to encode
 	 * @return string
+	 * @deprecated 32.0.0 use \OCP\Util::encodePath instead
 	 */
 	public static function encodePath($component) {
 		$encoded = rawurlencode($component);
@@ -692,86 +688,6 @@ public static function encodePath($component) {
 		return $encoded;
 	}
 
-
-	public function createHtaccessTestFile(\OCP\IConfig $config) {
-		// php dev server does not support htaccess
-		if (php_sapi_name() === 'cli-server') {
-			return false;
-		}
-
-		// testdata
-		$fileName = '/htaccesstest.txt';
-		$testContent = 'This is used for testing whether htaccess is properly enabled to disallow access from the outside. This file can be safely removed.';
-
-		// creating a test file
-		$testFile = $config->getSystemValueString('datadirectory', OC::$SERVERROOT . '/data') . '/' . $fileName;
-
-		if (file_exists($testFile)) {// already running this test, possible recursive call
-			return false;
-		}
-
-		$fp = @fopen($testFile, 'w');
-		if (!$fp) {
-			throw new \OCP\HintException('Can\'t create test file to check for working .htaccess file.',
-				'Make sure it is possible for the web server to write to ' . $testFile);
-		}
-		fwrite($fp, $testContent);
-		fclose($fp);
-
-		return $testContent;
-	}
-
-	/**
-	 * Check if the .htaccess file is working
-	 *
-	 * @param \OCP\IConfig $config
-	 * @return bool
-	 * @throws Exception
-	 * @throws \OCP\HintException If the test file can't get written.
-	 */
-	public function isHtaccessWorking(\OCP\IConfig $config) {
-		if (\OC::$CLI || !$config->getSystemValueBool('check_for_working_htaccess', true)) {
-			return true;
-		}
-
-		$testContent = $this->createHtaccessTestFile($config);
-		if ($testContent === false) {
-			return false;
-		}
-
-		$fileName = '/htaccesstest.txt';
-		$testFile = $config->getSystemValueString('datadirectory', OC::$SERVERROOT . '/data') . '/' . $fileName;
-
-		// accessing the file via http
-		$url = \OC::$server->getURLGenerator()->getAbsoluteURL(OC::$WEBROOT . '/data' . $fileName);
-		try {
-			$content = \OC::$server->get(IClientService::class)->newClient()->get($url)->getBody();
-		} catch (\Exception $e) {
-			$content = false;
-		}
-
-		if (str_starts_with($url, 'https:')) {
-			$url = 'http:' . substr($url, 6);
-		} else {
-			$url = 'https:' . substr($url, 5);
-		}
-
-		try {
-			$fallbackContent = \OC::$server->get(IClientService::class)->newClient()->get($url)->getBody();
-		} catch (\Exception $e) {
-			$fallbackContent = false;
-		}
-
-		// cleanup
-		@unlink($testFile);
-
-		/*
-		 * If the content is not equal to test content our .htaccess
-		 * is working as required
-		 */
-		return $content !== $testContent && $fallbackContent !== $testContent;
-	}
-
 	/**
 	 * Check if current locale is non-UTF8
 	 *
@@ -791,9 +707,9 @@ private static function isNonUTF8Locale() {
 	 * Check if the setlocale call does not work. This can happen if the right
 	 * local packages are not available on the server.
 	 *
-	 * @return bool
+	 * @internal
 	 */
-	public static function isSetLocaleWorking() {
+	public static function isSetLocaleWorking(): bool {
 		if (self::isNonUTF8Locale()) {
 			// Borrowed from \Patchwork\Utf8\Bootup::initLocale
 			setlocale(LC_ALL, 'C.UTF-8', 'C');
@@ -811,9 +727,9 @@ public static function isSetLocaleWorking() {
 	/**
 	 * Check if it's possible to get the inline annotations
 	 *
-	 * @return bool
+	 * @internal
 	 */
-	public static function isAnnotationsWorking() {
+	public static function isAnnotationsWorking(): bool {
 		if (PHP_VERSION_ID >= 80300) {
 			/** @psalm-suppress UndefinedMethod */
 			$reflection = \ReflectionMethod::createFromMethodName(__METHOD__);
@@ -828,9 +744,9 @@ public static function isAnnotationsWorking() {
 	/**
 	 * Check if the PHP module fileinfo is loaded.
 	 *
-	 * @return bool
+	 * @internal
 	 */
-	public static function fileInfoLoaded() {
+	public static function fileInfoLoaded(): bool {
 		return function_exists('finfo_open');
 	}
 
@@ -900,6 +816,7 @@ public static function normalizeUnicode(string $value): string {
 	 * @param \OC\SystemConfig $config
 	 * @return bool whether the core or any app needs an upgrade
 	 * @throws \OCP\HintException When the upgrade from the given version is not allowed
+	 * @deprecated 32.0.0 Use \OCP\Util::needUpgrade instead
 	 */
 	public static function needUpgrade(\OC\SystemConfig $config) {
 		if ($config->getValue('installed', false)) {
diff --git a/lib/public/Share/IManager.php b/lib/public/Share/IManager.php
index 23713f2e462f9..89d6f5e4a873b 100644
--- a/lib/public/Share/IManager.php
+++ b/lib/public/Share/IManager.php
@@ -485,11 +485,9 @@ public function currentUserCanEnumerateTargetUser(?IUser $currentUser, IUser $ta
 	/**
 	 * Check if sharing is disabled for the given user
 	 *
-	 * @param string $userId
-	 * @return bool
 	 * @since 9.0.0
 	 */
-	public function sharingDisabledForUser($userId);
+	public function sharingDisabledForUser(?string $userId): bool;
 
 	/**
 	 * Check if outgoing server2server shares are allowed
diff --git a/lib/public/Util.php b/lib/public/Util.php
index 65776bd15a7f0..14663abd62f14 100644
--- a/lib/public/Util.php
+++ b/lib/public/Util.php
@@ -78,19 +78,16 @@ public static function getChannel() {
 	 *
 	 * @return boolean
 	 * @since 7.0.0
-	 * @deprecated 9.1.0 Use \OC::$server->get(\OCP\Share\IManager::class)->sharingDisabledForUser
+	 * @deprecated 9.1.0 Use Server::get(\OCP\Share\IManager::class)->sharingDisabledForUser
 	 */
 	public static function isSharingDisabledForUser() {
 		if (self::$shareManager === null) {
-			self::$shareManager = \OC::$server->get(IManager::class);
+			self::$shareManager = Server::get(IManager::class);
 		}
 
-		$user = \OC::$server->getUserSession()->getUser();
-		if ($user !== null) {
-			$user = $user->getUID();
-		}
+		$user = Server::get(\OCP\IUserSession::class)->getUser();
 
-		return self::$shareManager->sharingDisabledForUser($user);
+		return self::$shareManager->sharingDisabledForUser($user?->getUID());
 	}
 
 	/**
@@ -102,13 +99,15 @@ public static function getL10N(string $application, ?string $language = null): I
 	}
 
 	/**
-	 * add a css file
-	 * @param string $application
-	 * @param string $file
+	 * Add a css file
+	 *
+	 * @param string $application application id
+	 * @param ?string $file filename
+	 * @param bool $prepend prepend the style to the beginning of the list
 	 * @since 4.0.0
 	 */
-	public static function addStyle($application, $file = null): void {
-		\OC_Util::addStyle($application, $file);
+	public static function addStyle(string $application, ?string $file = null, bool $prepend = false): void {
+		\OC_Util::addStyle($application, $file, $prepend);
 	}
 
 	/**
diff --git a/tests/lib/UtilTest.php b/tests/lib/UtilTest.php
index fcb77332fcc70..0063a991e48c1 100644
--- a/tests/lib/UtilTest.php
+++ b/tests/lib/UtilTest.php
@@ -42,25 +42,25 @@ public function testSanitizeHTML(): void {
 				'And It Even May &lt;strong&gt;Nest&lt;/strong&gt;'
 			],
 		];
-		$result = OC_Util::sanitizeHTML($badArray);
+		$result = Util::sanitizeHTML($badArray);
 		$this->assertEquals($goodArray, $result);
 
 		$badString = '<img onload="alert(1)" />';
-		$result = OC_Util::sanitizeHTML($badString);
+		$result = Util::sanitizeHTML($badString);
 		$this->assertEquals('&lt;img onload=&quot;alert(1)&quot; /&gt;', $result);
 
 		$badString = "<script>alert('Hacked!');</script>";
-		$result = OC_Util::sanitizeHTML($badString);
+		$result = Util::sanitizeHTML($badString);
 		$this->assertEquals('&lt;script&gt;alert(&#039;Hacked!&#039;);&lt;/script&gt;', $result);
 
 		$goodString = 'This is a good string without HTML.';
-		$result = OC_Util::sanitizeHTML($goodString);
+		$result = Util::sanitizeHTML($goodString);
 		$this->assertEquals('This is a good string without HTML.', $result);
 	}
 
 	public function testEncodePath(): void {
 		$component = '/§#@test%&^ä/-child';
-		$result = OC_Util::encodePath($component);
+		$result = Util::encodePath($component);
 		$this->assertEquals('/%C2%A7%23%40test%25%26%5E%C3%A4/-child', $result);
 	}
 
@@ -295,12 +295,12 @@ public function testAddTranslations(): void {
 	}
 
 	public function testAddStyle(): void {
-		\OC_Util::addStyle('core', 'myFancyCSSFile1');
-		\OC_Util::addStyle('myApp', 'myFancyCSSFile2');
-		\OC_Util::addStyle('core', 'myFancyCSSFile0', true);
-		\OC_Util::addStyle('core', 'myFancyCSSFile10', true);
+		Util::addStyle('core', 'myFancyCSSFile1');
+		Util::addStyle('myApp', 'myFancyCSSFile2');
+		Util::addStyle('core', 'myFancyCSSFile0', true);
+		Util::addStyle('core', 'myFancyCSSFile10', true);
 		// add duplicate
-		\OC_Util::addStyle('core', 'myFancyCSSFile1');
+		Util::addStyle('core', 'myFancyCSSFile1');
 
 		$this->assertEquals([], Util::getScripts());
 		$this->assertEquals([