Complete PHPStan Level 6 (#5305)

* Complete PHPStan Level 6
Fix https://github.com/FreshRSS/FreshRSS/issues/4112
And initiate PHPStan Level 7

* PHPStan Level 6 for tests
* Use phpstan/phpstan-phpunit
* Update to PHPStan version 1.10

* Fix mixed bug

* Fix mixed return bug

* Fix paginator bug

* Fix FreshRSS_UserConfiguration

* A couple more Minz_Configuration bug fixes

* A few trivial PHPStan Level 7 fixes

* A few more simple PHPStan Level 7

* More files passing PHPStan Level 7
Add interface to replace removed class from https://github.com/FreshRSS/FreshRSS/pull/5251

* A few more PHPStan Level 7 preparations

* A few last details

45 files changed, 273 insertions, 260 deletions

diff --git a/app/Controllers/categoryController.php b/app/Controllers/categoryController.php
index 91cd92787..0ca1bbbcd 100644
--- a/app/Controllers/categoryController.php
+++ b/app/Controllers/categoryController.php
@@ -33,7 +33,7 @@ class FreshRSS_category_Controller extends FreshRSS_ActionController {
 		$url_redirect = array('c' => 'subscription', 'a' => 'add');
 
 		$limits = FreshRSS_Context::$system_conf->limits;
-		$this->view->categories = $catDAO->listCategories(false);
+		$this->view->categories = $catDAO->listCategories(false) ?: [];
 
 		if (count($this->view->categories) >= $limits['max_categories']) {
 			Minz_Request::bad(_t('feedback.sub.category.over_max', $limits['max_categories']), $url_redirect);
@@ -231,7 +231,7 @@ class FreshRSS_category_Controller extends FreshRSS_ActionController {
 
 			if (Minz_Request::paramBoolean('ajax')) {
 				Minz_Request::setGoodNotification(_t('feedback.sub.category.updated'));
-				$this->view->_layout(false);
+				$this->view->_layout(null);
 			} else {
 				if ($ok) {
 					Minz_Request::good(_t('feedback.sub.category.updated'), $url_redirect);
diff --git a/app/Controllers/configureController.php b/app/Controllers/configureController.php
index 667c2da74..87d9e4426 100644
--- a/app/Controllers/configureController.php
+++ b/app/Controllers/configureController.php
@@ -264,7 +264,7 @@ class FreshRSS_configure_Controller extends FreshRSS_ActionController {
 		FreshRSS_Context::$user_conf->volatile = $volatile;
 
 		$entryDAO = FreshRSS_Factory::createEntryDao();
-		$this->view->nb_total = $entryDAO->count();
+		$this->view->nb_total = $entryDAO->count() ?: 0;
 
 		$databaseDAO = FreshRSS_Factory::createDatabaseDAO();
 		$this->view->size_user = $databaseDAO->size();
@@ -338,7 +338,7 @@ class FreshRSS_configure_Controller extends FreshRSS_ActionController {
 	 * applied to the selected query.
 	 */
 	public function queryAction(): void {
-		$this->view->_layout(false);
+		$this->view->_layout(null);
 
 		$id = Minz_Request::paramInt('id');
 		if ($id !== 0 || !isset(FreshRSS_Context::$user_conf->queries[$id])) {
diff --git a/app/Controllers/entryController.php b/app/Controllers/entryController.php
index 7a30f94de..ff995b12f 100644
--- a/app/Controllers/entryController.php
+++ b/app/Controllers/entryController.php
@@ -24,7 +24,7 @@ class FreshRSS_entry_Controller extends FreshRSS_ActionController {
 		// If ajax request, we do not print layout
 		$this->ajax = Minz_Request::paramBoolean('ajax');
 		if ($this->ajax) {
-			$this->view->_layout(false);
+			$this->view->_layout(null);
 			Minz_Request::_param('ajax');
 		}
 	}
@@ -107,7 +107,7 @@ class FreshRSS_entry_Controller extends FreshRSS_ActionController {
 			$ids = is_array($id) ? $id : array($id);
 			$entryDAO->markRead($ids, $is_read);
 			$tagDAO = FreshRSS_Factory::createTagDao();
-			$tagsForEntries = $tagDAO->getTagsForEntries($ids);
+			$tagsForEntries = $tagDAO->getTagsForEntries($ids) ?: [];
 			$tags = array();
 			foreach ($tagsForEntries as $line) {
 				$tags['t_' . $line['id_tag']][] = $line['id_entry'];
diff --git a/app/Controllers/extensionController.php b/app/Controllers/extensionController.php
index b482b1a35..4b440327d 100644
--- a/app/Controllers/extensionController.php
+++ b/app/Controllers/extensionController.php
@@ -79,7 +79,7 @@ class FreshRSS_extension_Controller extends FreshRSS_ActionController {
 	 */
 	public function configureAction(): void {
 		if (Minz_Request::paramBoolean('ajax')) {
-			$this->view->_layout(false);
+			$this->view->_layout(null);
 		} else {
 			$this->indexAction();
 			$this->view->_path('extension/index.phtml');
@@ -143,7 +143,7 @@ class FreshRSS_extension_Controller extends FreshRSS_ActionController {
 
 			if ($conf !== null && $res === true) {
 				$ext_list = $conf->extensions_enabled;
-				$ext_list = array_filter($ext_list, function($key) use($type) {
+				$ext_list = array_filter($ext_list, static function(string $key) use($type) {
 					// Remove from list the extensions that have disappeared or changed type
 					$extension = Minz_ExtensionManager::findExtension($key);
 					return $extension !== null && $extension->getType() === $type;
@@ -205,7 +205,7 @@ class FreshRSS_extension_Controller extends FreshRSS_ActionController {
 
 			if ($conf !== null && $res === true) {
 				$ext_list = $conf->extensions_enabled;
-				$ext_list = array_filter($ext_list, function($key) use($type) {
+				$ext_list = array_filter($ext_list, static function(string $key) use($type) {
 					// Remove from list the extensions that have disappeared or changed type
 					$extension = Minz_ExtensionManager::findExtension($key);
 					return $extension !== null && $extension->getType() === $type;
diff --git a/app/Controllers/feedController.php b/app/Controllers/feedController.php
index 39a1c7289..15bf0128b 100644
--- a/app/Controllers/feedController.php
+++ b/app/Controllers/feedController.php
@@ -262,7 +262,7 @@ class FreshRSS_feed_Controller extends FreshRSS_ActionController {
 			FreshRSS_View::prependTitle(_t('sub.feed.title_add') . ' · ');
 
 			$catDAO = FreshRSS_Factory::createCategoryDao();
-			$this->view->categories = $catDAO->listCategories(false);
+			$this->view->categories = $catDAO->listCategories(false) ?: [];
 			$this->view->feed = new FreshRSS_Feed($url);
 			try {
 				// We try to get more information about the feed.
@@ -316,7 +316,8 @@ class FreshRSS_feed_Controller extends FreshRSS_ActionController {
 	/**
 	 * @return array{0:int,1:FreshRSS_Feed|false,2:int}
 	 */
-	public static function actualizeFeed(int $feed_id, string $feed_url, bool $force, ?SimplePie $simplePiePush = null, bool $noCommit = false, int $maxFeeds = 10) {
+	public static function actualizeFeed(int $feed_id, string $feed_url, bool $force, ?SimplePie $simplePiePush = null,
+		bool $noCommit = false, int $maxFeeds = 10): array {
 		@set_time_limit(300);
 
 		$feedDAO = FreshRSS_Factory::createFeedDao();
@@ -666,7 +667,7 @@ class FreshRSS_feed_Controller extends FreshRSS_ActionController {
 			// are several updated feeds.
 			Minz_Request::setGoodNotification(_t('feedback.sub.feed.actualizeds'));
 			// No layout in ajax request.
-			$this->view->_layout(false);
+			$this->view->_layout(null);
 		} else {
 			// Redirect to the main page with correct notification.
 			if ($updated_feeds === 1) {
@@ -903,7 +904,7 @@ class FreshRSS_feed_Controller extends FreshRSS_ActionController {
 		$this->view->selectorSuccess = false;
 		$this->view->htmlContent = '';
 
-		$this->view->_layout(false);
+		$this->view->_layout(null);
 
 		$this->_csp([
 			'default-src' => "'self'",
diff --git a/app/Controllers/importExportController.php b/app/Controllers/importExportController.php
index 2df185398..4939a0748 100644
--- a/app/Controllers/importExportController.php
+++ b/app/Controllers/importExportController.php
@@ -226,7 +226,7 @@ class FreshRSS_importExport_Controller extends FreshRSS_ActionController {
 		unset($table['article']);
 		for ($i = count($table['items']) - 1; $i >= 0; $i--) {
 			$item = (array)($table['items'][$i]);
-			$item = array_filter($item, function ($v) {
+			$item = array_filter($item, static function ($v) {
 					// Filter out empty properties, potentially reported as empty objects
 					return (is_string($v) && trim($v) !== '') || !empty($v);
 				});
@@ -267,7 +267,7 @@ class FreshRSS_importExport_Controller extends FreshRSS_ActionController {
 	 *
 	 * $article_file the JSON file content.
 	 * true if articles from the file must be starred.
-	 * @return boolean false if an error occurred, true otherwise.
+	 * @return bool false if an error occurred, true otherwise.
 	 */
 	private function importJson(string $article_file, bool $starred = false): bool {
 		$article_object = json_decode($article_file, true);
@@ -575,10 +575,8 @@ class FreshRSS_importExport_Controller extends FreshRSS_ActionController {
 	 *   - export_starred (default: false)
 	 *   - export_labelled (default: false)
 	 *   - export_feeds (default: array()) a list of feed ids
-	 *
-	 * @return void|null
 	 */
-	public function exportAction() {
+	public function exportAction(): void {
 		if (!Minz_Request::isPost()) {
 			Minz_Request::forward(['c' => 'importExport', 'a' => 'index'], true);
 			return;
@@ -654,7 +652,7 @@ class FreshRSS_importExport_Controller extends FreshRSS_ActionController {
 		header('Content-Type: ' . $content_type);
 		header('Content-disposition: attachment; filename="' . $filename . '"');
 
-		$this->view->_layout(false);
+		$this->view->_layout(null);
 		$this->view->content = $content;
 	}
 
diff --git a/app/Controllers/indexController.php b/app/Controllers/indexController.php
index 17aee3585..64371c530 100644
--- a/app/Controllers/indexController.php
+++ b/app/Controllers/indexController.php
@@ -58,10 +58,10 @@ class FreshRSS_index_Controller extends FreshRSS_ActionController {
 
 		FreshRSS_Context::$id_max = time() . '000000';
 
-		$this->view->callbackBeforeFeeds = function ($view) {
+		$this->view->callbackBeforeFeeds = function (FreshRSS_View $view) {
 			try {
 				$tagDAO = FreshRSS_Factory::createTagDao();
-				$view->tags = $tagDAO->listTags(true);
+				$view->tags = $tagDAO->listTags(true) ?: [];
 				$view->nbUnreadTags = 0;
 				foreach ($view->tags as $tag) {
 					$view->nbUnreadTags += $tag->nbUnread();
@@ -71,7 +71,7 @@ class FreshRSS_index_Controller extends FreshRSS_ActionController {
 			}
 		};
 
-		$this->view->callbackBeforeEntries = function ($view) {
+		$this->view->callbackBeforeEntries = function (FreshRSS_View $view) {
 			try {
 				FreshRSS_Context::$number++;	//+1 for articles' page
 				$view->entries = FreshRSS_index_Controller::listEntriesByContext();
@@ -83,7 +83,7 @@ class FreshRSS_index_Controller extends FreshRSS_ActionController {
 			}
 		};
 
-		$this->view->callbackBeforePagination = function ($view, $nbEntries, $lastEntry) {
+		$this->view->callbackBeforePagination = function (?FreshRSS_View $view, int $nbEntries, FreshRSS_Entry $lastEntry) {
 			if ($nbEntries >= FreshRSS_Context::$number) {
 				//We have enough entries: we discard the last one to use it for the next articles' page
 				ob_clean();
@@ -170,7 +170,7 @@ class FreshRSS_index_Controller extends FreshRSS_ActionController {
 		// No layout for RSS output.
 		$this->view->rss_url = PUBLIC_TO_INDEX_PATH . '/' . (empty($_SERVER['QUERY_STRING']) ? '' : '?' . $_SERVER['QUERY_STRING']);
 		$this->view->rss_title = FreshRSS_Context::$name . ' | ' . FreshRSS_View::title();
-		$this->view->_layout(false);
+		$this->view->_layout(null);
 		header('Content-Type: application/rss+xml; charset=utf-8');
 	}
 
@@ -238,7 +238,7 @@ class FreshRSS_index_Controller extends FreshRSS_ActionController {
 		}
 
 		// No layout for OPML output.
-		$this->view->_layout(false);
+		$this->view->_layout(null);
 		header('Content-Type: application/xml; charset=utf-8');
 	}
 
diff --git a/app/Controllers/javascriptController.php b/app/Controllers/javascriptController.php
index d7c600113..ce25d03c9 100644
--- a/app/Controllers/javascriptController.php
+++ b/app/Controllers/javascriptController.php
@@ -3,7 +3,7 @@
 class FreshRSS_javascript_Controller extends FreshRSS_ActionController {
 
 	public function firstAction(): void {
-		$this->view->_layout(false);
+		$this->view->_layout(null);
 	}
 
 	public function actualizeAction(): void {
@@ -20,9 +20,9 @@ class FreshRSS_javascript_Controller extends FreshRSS_ActionController {
 	public function nbUnreadsPerFeedAction(): void {
 		header('Content-Type: application/json; charset=UTF-8');
 		$catDAO = FreshRSS_Factory::createCategoryDao();
-		$this->view->categories = $catDAO->listCategories(true, false);
+		$this->view->categories = $catDAO->listCategories(true, false) ?: [];
 		$tagDAO = FreshRSS_Factory::createTagDao();
-		$this->view->tags = $tagDAO->listTags(true);
+		$this->view->tags = $tagDAO->listTags(true) ?: [];
 	}
 
 	//For Web-form login
diff --git a/app/Controllers/statsController.php b/app/Controllers/statsController.php
index cd9a247c4..0fc6490f8 100644
--- a/app/Controllers/statsController.php
+++ b/app/Controllers/statsController.php
@@ -26,7 +26,7 @@ class FreshRSS_stats_Controller extends FreshRSS_ActionController {
 
 		$catDAO->checkDefault();
 		$feedDAO->updateTTL();
-		$this->view->categories = $catDAO->listSortedCategories(false);
+		$this->view->categories = $catDAO->listSortedCategories(false) ?: [];
 		$this->view->default_category = $catDAO->getDefault();
 
 		FreshRSS_View::prependTitle(_t('admin.stats.title') . ' · ');
@@ -207,7 +207,7 @@ class FreshRSS_stats_Controller extends FreshRSS_ActionController {
 			$id = null;
 		}
 
-		$this->view->categories 	= $categoryDAO->listCategories();
+		$this->view->categories 	= $categoryDAO->listCategories() ?: [];
 		$this->view->feed 			= $id === null ? null : $feedDAO->searchById($id);
 		$this->view->days 			= $statsDAO->getDays();
 		$this->view->months 		= $statsDAO->getMonths();
diff --git a/app/Controllers/subscriptionController.php b/app/Controllers/subscriptionController.php
index e0a8d4ff4..d96cb02e1 100644
--- a/app/Controllers/subscriptionController.php
+++ b/app/Controllers/subscriptionController.php
@@ -19,7 +19,7 @@ class FreshRSS_subscription_Controller extends FreshRSS_ActionController {
 
 		$catDAO->checkDefault();
 		$feedDAO->updateTTL();
-		$this->view->categories = $catDAO->listSortedCategories(false, true);
+		$this->view->categories = $catDAO->listSortedCategories(false, true) ?: [];
 		$this->view->default_category = $catDAO->getDefault();
 
 		$signalError = false;
@@ -90,7 +90,7 @@ class FreshRSS_subscription_Controller extends FreshRSS_ActionController {
 	 */
 	public function feedAction(): void {
 		if (Minz_Request::paramBoolean('ajax')) {
-			$this->view->_layout(false);
+			$this->view->_layout(null);
 		} else {
 			FreshRSS_View::appendScript(Minz_Url::display('/scripts/feed.js?' . @filemtime(PUBLIC_PATH . '/scripts/feed.js')));
 		}
@@ -200,7 +200,7 @@ class FreshRSS_subscription_Controller extends FreshRSS_ActionController {
 				]);
 			}
 
-			$feed->_filtersAction('read', preg_split('/[\n\r]+/', Minz_Request::paramString('filteractions_read')));
+			$feed->_filtersAction('read', preg_split('/[\n\r]+/', Minz_Request::paramString('filteractions_read')) ?: []);
 
 			$feed->_kind(Minz_Request::paramInt('feed_kind') ?: FreshRSS_Feed::KIND_RSS);
 			if ($feed->kind() === FreshRSS_Feed::KIND_HTML_XPATH || $feed->kind() === FreshRSS_Feed::KIND_XML_XPATH) {
@@ -235,8 +235,8 @@ class FreshRSS_subscription_Controller extends FreshRSS_ActionController {
 				'name' => Minz_Request::paramString('name'),
 				'kind' => $feed->kind(),
 				'description' => sanitizeHTML(Minz_Request::paramString('description', true)),
-				'website' => checkUrl(Minz_Request::paramString('website')),
-				'url' => checkUrl(Minz_Request::paramString('url')),
+				'website' => checkUrl(Minz_Request::paramString('website')) ?: '',
+				'url' => checkUrl(Minz_Request::paramString('url')) ?: '',
 				'category' => Minz_Request::paramInt('category'),
 				'pathEntries' => Minz_Request::paramString('path_entries'),
 				'priority' => Minz_Request::paramTernary('priority') === null ? FreshRSS_Feed::PRIORITY_MAIN_STREAM : Minz_Request::paramInt('priority'),
@@ -283,7 +283,7 @@ class FreshRSS_subscription_Controller extends FreshRSS_ActionController {
 	}
 
 	public function categoryAction(): void {
-		$this->view->_layout(false);
+		$this->view->_layout(null);
 
 		$categoryDAO = FreshRSS_Factory::createCategoryDao();
 
diff --git a/app/Controllers/tagController.php b/app/Controllers/tagController.php
index e4048238c..7a89b2b84 100644
--- a/app/Controllers/tagController.php
+++ b/app/Controllers/tagController.php
@@ -23,7 +23,7 @@ class FreshRSS_tag_Controller extends FreshRSS_ActionController {
 		// If ajax request, we do not print layout
 		$this->ajax = Minz_Request::paramBoolean('ajax');
 		if ($this->ajax) {
-			$this->view->_layout(false);
+			$this->view->_layout(null);
 			Minz_Request::_param('ajax');
 		}
 	}
@@ -39,7 +39,7 @@ class FreshRSS_tag_Controller extends FreshRSS_ActionController {
 			$checked = Minz_Request::paramTernary('checked');
 			if ($id_entry != '') {
 				$tagDAO = FreshRSS_Factory::createTagDao();
-				if ($id_tag === 0 && $name_tag !== '' && $checked) {
+				if ($id_tag == 0 && $name_tag !== '' && $checked) {
 					if ($existing_tag = $tagDAO->searchByName($name_tag)) {
 						// Use existing tag
 						$tagDAO->tagEntry($existing_tag->id(), $id_entry, $checked);
@@ -48,7 +48,7 @@ class FreshRSS_tag_Controller extends FreshRSS_ActionController {
 						$id_tag = $tagDAO->addTag(array('name' => $name_tag));
 					}
 				}
-				if ($id_tag !== 0) {
+				if ($id_tag != false) {
 					$tagDAO->tagEntry($id_tag, $id_entry, $checked);
 				}
 			}
@@ -82,12 +82,12 @@ class FreshRSS_tag_Controller extends FreshRSS_ActionController {
 	}
 
 	public function getTagsForEntryAction(): void {
-		$this->view->_layout(false);
+		$this->view->_layout(null);
 		header('Content-Type: application/json; charset=UTF-8');
 		header('Cache-Control: private, no-cache, no-store, must-revalidate');
 		$id_entry = Minz_Request::paramString('id_entry');
 		$tagDAO = FreshRSS_Factory::createTagDao();
-		$this->view->tagsForEntry = $tagDAO->getTagsForEntry($id_entry);
+		$this->view->tagsForEntry = $tagDAO->getTagsForEntry($id_entry) ?: [];
 	}
 
 	public function addAction(): void {
@@ -110,11 +110,10 @@ class FreshRSS_tag_Controller extends FreshRSS_ActionController {
 	}
 
 	/**
-	 * @return void|null
 	 * @throws Minz_ConfigurationNamespaceException
 	 * @throws Minz_PDOConnectionException
 	 */
-	public function renameAction() {
+	public function renameAction(): void {
 		if (!Minz_Request::isPost()) {
 			Minz_Error::error(405);
 		}
@@ -145,6 +144,6 @@ class FreshRSS_tag_Controller extends FreshRSS_ActionController {
 
 	public function indexAction(): void {
 		$tagDAO = FreshRSS_Factory::createTagDao();
-		$this->view->tags = $tagDAO->listTags();
+		$this->view->tags = $tagDAO->listTags() ?: [];
 	}
 }
diff --git a/app/Models/Auth.php b/app/Models/Auth.php
index 8fd06b24d..e868e1b4f 100644
--- a/app/Models/Auth.php
+++ b/app/Models/Auth.php
@@ -135,9 +135,9 @@ class FreshRSS_Auth {
 	 * Returns if current user has access to the given scope.
 	 *
 	 * @param string $scope general (default) or admin
-	 * @return boolean true if user has corresponding access, false else.
+	 * @return bool true if user has corresponding access, false else.
 	 */
-	public static function hasAccess($scope = 'general'): bool {
+	public static function hasAccess(string $scope = 'general'): bool {
 		if (FreshRSS_Context::$user_conf == null) {
 			return false;
 		}
@@ -154,7 +154,7 @@ class FreshRSS_Auth {
 		default:
 			$ok = false;
 		}
-		return $ok;
+		return (bool)$ok;
 	}
 
 	/**
diff --git a/app/Models/BooleanSearch.php b/app/Models/BooleanSearch.php
index 89e6e3ee2..f4979b22b 100644
--- a/app/Models/BooleanSearch.php
+++ b/app/Models/BooleanSearch.php
@@ -230,7 +230,7 @@ class FreshRSS_BooleanSearch {
 		if ($input == '') {
 			return;
 		}
-		$splits = preg_split('/\b(OR)\b/i', $input, -1, PREG_SPLIT_DELIM_CAPTURE);
+		$splits = preg_split('/\b(OR)\b/i', $input, -1, PREG_SPLIT_DELIM_CAPTURE) ?: [];
 
 		$segment = '';
 		$ns = count($splits);
diff --git a/app/Models/Category.php b/app/Models/Category.php
index 737544481..4e28b1741 100644
--- a/app/Models/Category.php
+++ b/app/Models/Category.php
@@ -262,7 +262,7 @@ class FreshRSS_Category extends Minz_Model {
 		$catDAO = FreshRSS_Factory::createCategoryDao();
 		$catDAO->updateLastUpdate($this->id(), !$ok);
 
-		return $ok;
+		return (bool)$ok;
 	}
 
 	private function sortFeeds(): void {
diff --git a/app/Models/CategoryDAO.php b/app/Models/CategoryDAO.php
index 64b14ffb7..29593ce5f 100644
--- a/app/Models/CategoryDAO.php
+++ b/app/Models/CategoryDAO.php
@@ -477,7 +477,7 @@ SQL;
 			$cat->_id($previousLine['c_id']);
 			$cat->_kind($previousLine['c_kind']);
 			$cat->_lastUpdate($previousLine['c_last_update'] ?? 0);
-			$cat->_error($previousLine['c_error'] ?? false);
+			$cat->_error($previousLine['c_error'] ?? 0);
 			$cat->_attributes('', $previousLine['c_attributes']);
 			$list[$previousLine['c_id']] = $cat;
 		}
diff --git a/app/Models/Context.php b/app/Models/Context.php
index b2631291a..03006cbbf 100644
--- a/app/Models/Context.php
+++ b/app/Models/Context.php
@@ -110,10 +110,9 @@ final class FreshRSS_Context {
 
 	/**
 	 * Initialize the context for the current user.
-	 * @return FreshRSS_UserConfiguration|false
 	 * @throws Minz_ConfigurationParamException
 	 */
-	public static function initUser(string $username = '', bool $userMustExist = true) {
+	public static function initUser(string $username = '', bool $userMustExist = true): ?FreshRSS_UserConfiguration {
 		FreshRSS_Context::$user_conf = null;
 		if (!isset($_SESSION)) {
 			Minz_Session::init('FreshRSS');
@@ -145,7 +144,7 @@ final class FreshRSS_Context {
 		Minz_Session::unlock();
 
 		if (FreshRSS_Context::$user_conf == null) {
-			return false;
+			return null;
 		}
 
 		FreshRSS_Context::$search = new FreshRSS_BooleanSearch('');
@@ -249,8 +248,8 @@ final class FreshRSS_Context {
 	/**
 	 * Return the current get as a string or an array.
 	 *
-	 * If $array is true, the first item of the returned value is 'f' or 'c' and
-	 * the second is the id.
+	 * If $array is true, the first item of the returned value is 'f' or 'c' or 't' and the second is the id.
+	 * @phpstan-return ($asArray is true ? array{'c'|'f'|'t',bool|int} : string)
 	 * @return string|array{string,bool|int}
 	 */
 	public static function currentGet(bool $asArray = false) {
diff --git a/app/Models/DatabaseDAO.php b/app/Models/DatabaseDAO.php
index 28dd36cd9..aeac6f435 100644
--- a/app/Models/DatabaseDAO.php
+++ b/app/Models/DatabaseDAO.php
@@ -79,7 +79,7 @@ class FreshRSS_DatabaseDAO extends Minz_ModelPdo {
 			$ok &= in_array($c['name'], $schema);
 		}
 
-		return $ok;
+		return (bool)$ok;
 	}
 
 	public function categoryIsCorrect(): bool {
diff --git a/app/Models/DatabaseDAOSQLite.php b/app/Models/DatabaseDAOSQLite.php
index 3fab1134d..0909613a7 100644
--- a/app/Models/DatabaseDAOSQLite.php
+++ b/app/Models/DatabaseDAOSQLite.php
@@ -8,7 +8,10 @@ class FreshRSS_DatabaseDAOSQLite extends FreshRSS_DatabaseDAO {
 	public function tablesAreCorrect(): bool {
 		$sql = 'SELECT name FROM sqlite_master WHERE type="table"';
 		$stm = $this->pdo->query($sql);
-		$res = $stm->fetchAll(PDO::FETCH_ASSOC);
+		$res = $stm ? $stm->fetchAll(PDO::FETCH_ASSOC) : false;
+		if ($res === false) {
+			return false;
+		}
 
 		$tables = array(
 			$this->pdo->prefix() . 'category' => false,
@@ -29,7 +32,7 @@ class FreshRSS_DatabaseDAOSQLite extends FreshRSS_DatabaseDAO {
 	public function getSchema(string $table): array {
 		$sql = 'PRAGMA table_info(' . $table . ')';
 		$stm = $this->pdo->query($sql);
-		return $this->listDaoToSchema($stm->fetchAll(PDO::FETCH_ASSOC));
+		return $stm ? $this->listDaoToSchema($stm->fetchAll(PDO::FETCH_ASSOC) ?: []) : [];
 	}
 
 	public function entryIsCorrect(): bool {
@@ -62,7 +65,7 @@ class FreshRSS_DatabaseDAOSQLite extends FreshRSS_DatabaseDAO {
 	public function size(bool $all = false): int {
 		$sum = 0;
 		if ($all) {
-			foreach (glob(DATA_PATH . '/users/*/db.sqlite') as $filename) {
+			foreach (glob(DATA_PATH . '/users/*/db.sqlite') ?: [] as $filename) {
 				$sum += @filesize($filename);
 			}
 		} else {
diff --git a/app/Models/Entry.php b/app/Models/Entry.php
index d208b07ec..20f17d1c7 100644
--- a/app/Models/Entry.php
+++ b/app/Models/Entry.php
@@ -106,7 +106,7 @@ class FreshRSS_Entry extends Minz_Model {
 		return $this->authors(true);
 	}
 	/**
-	 * @phpstan return ($asString ? string : array<string>)
+	 * @phpstan-return ($asString is true ? string : array<string>)
 	 * @return string|array<string>
 	 */
 	public function authors(bool $asString = false) {
@@ -285,7 +285,7 @@ HTML;
 	/**
 	 * @return array<string,string>|null
 	 */
-	public function thumbnail(bool $searchEnclosures = true) {
+	public function thumbnail(bool $searchEnclosures = true): ?array {
 		$thumbnail = $this->attributes('thumbnail');
 		if (!empty($thumbnail['url'])) {
 			return $thumbnail;
@@ -352,7 +352,10 @@ HTML;
 		return $this->feedId;
 	}
 
-	/** @return string|array<string> */
+	/**
+	 * @phpstan-return ($asString is true ? string : array<string>)
+	 * @return string|array<string>
+	 */
 	public function tags(bool $asString = false) {
 		if ($asString) {
 			return $this->tags == null ? '' : '#' . implode(' #', $this->tags);
@@ -609,7 +612,7 @@ HTML;
 				}
 			}
 		}
-		return $ok;
+		return (bool)$ok;
 	}
 
 	/** @param array<string,int> $titlesAsRead  */
diff --git a/app/Models/EntryDAO.php b/app/Models/EntryDAO.php
index 9f24beb7c..1661bfd13 100644
--- a/app/Models/EntryDAO.php
+++ b/app/Models/EntryDAO.php
@@ -308,7 +308,7 @@ SQL;
 	 * there is an other way to do that.
 	 *
 	 * @param string|array<string> $ids
-	 * @return false|integer
+	 * @return int|false
 	 */
 	public function markFavorite($ids, bool $is_favorite = true) {
 		if (!is_array($ids)) {
@@ -348,12 +348,8 @@ SQL;
 	 * feeds from one category or on all feeds.
 	 *
 	 * @todo It can use the query builder refactoring to build that query
-	 *
-	 * @param false|integer $catId category ID
-	 * @param false|integer $feedId feed ID
-	 * @return boolean
 	 */
-	protected function updateCacheUnreads($catId = false, $feedId = false) {
+	protected function updateCacheUnreads(?int $catId = null, ?int $feedId = null): bool {
 		$sql = 'UPDATE `_feed` f '
 			. 'LEFT OUTER JOIN ('
 			.	'SELECT e.id_feed, '
@@ -365,13 +361,13 @@ SQL;
 			. 'SET f.`cache_nbUnreads`=COALESCE(x.nbUnreads, 0)';
 		$hasWhere = false;
 		$values = array();
-		if ($feedId !== false) {
+		if ($feedId != null) {
 			$sql .= ' WHERE';
 			$hasWhere = true;
 			$sql .= ' f.id=?';
 			$values[] = $feedId;
 		}
-		if ($catId !== false) {
+		if ($catId != null) {
 			$sql .= $hasWhere ? ' AND' : ' WHERE';
 			$hasWhere = true;
 			$sql .= ' f.category=?';
@@ -397,8 +393,8 @@ SQL;
 	 * same if it is an array or not.
 	 *
 	 * @param string|array<string> $ids
-	 * @param boolean $is_read
-	 * @return integer|false affected rows
+	 * @param bool $is_read
+	 * @return int|false affected rows
 	 */
 	public function markRead($ids, bool $is_read = true) {
 		FreshRSS_UserDAO::touch();
@@ -431,7 +427,7 @@ SQL;
 				return false;
 			}
 			$affected = $stm->rowCount();
-			if (($affected > 0) && (!$this->updateCacheUnreads(false, false))) {
+			if (($affected > 0) && (!$this->updateCacheUnreads(null, null))) {
 				return false;
 			}
 			return $affected;
@@ -469,7 +465,7 @@ SQL;
 	 * separated.
 	 *
 	 * @param string $idMax fail safe article ID
-	 * @return integer|false affected rows
+	 * @return int|false affected rows
 	 */
 	public function markReadEntries(string $idMax = '0', bool $onlyFavorites = false, int $priorityMin = 0,
 		?FreshRSS_BooleanSearch $filters = null, int $state = 0, bool $is_read = true) {
@@ -498,7 +494,7 @@ SQL;
 			return false;
 		}
 		$affected = $stm->rowCount();
-		if (($affected > 0) && (!$this->updateCacheUnreads(false, false))) {
+		if (($affected > 0) && (!$this->updateCacheUnreads(null, null))) {
 			return false;
 		}
 		return $affected;
@@ -511,9 +507,9 @@ SQL;
 	 *
 	 * If $idMax equals 0, a deprecated debug message is logged
 	 *
-	 * @param integer $id category ID
+	 * @param int $id category ID
 	 * @param string $idMax fail safe article ID
-	 * @return integer|false affected rows
+	 * @return int|false affected rows
 	 */
 	public function markReadCat(int $id, string $idMax = '0', ?FreshRSS_BooleanSearch $filters = null, int $state = 0, bool $is_read = true) {
 		FreshRSS_UserDAO::touch();
@@ -536,7 +532,7 @@ SQL;
 			return false;
 		}
 		$affected = $stm->rowCount();
-		if (($affected > 0) && (!$this->updateCacheUnreads($id, false))) {
+		if (($affected > 0) && (!$this->updateCacheUnreads($id, null))) {
 			return false;
 		}
 		return $affected;
@@ -549,9 +545,9 @@ SQL;
 	 *
 	 * If $idMax equals 0, a deprecated debug message is logged
 	 *
-	 * @param integer $id_feed feed ID
+	 * @param int $id_feed feed ID
 	 * @param string $idMax fail safe article ID
-	 * @return integer|false affected rows
+	 * @return int|false affected rows
 	 */
 	public function markReadFeed(int $id_feed, string $idMax = '0', ?FreshRSS_BooleanSearch $filters = null, int $state = 0, bool $is_read = true) {
 		FreshRSS_UserDAO::touch();
@@ -597,9 +593,9 @@ SQL;
 
 	/**
 	 * Mark all the articles in a tag as read.
-	 * @param integer $id tag ID, or empty for targeting any tag
+	 * @param int $id tag ID, or empty for targeting any tag
 	 * @param string $idMax max article ID
-	 * @return integer|false affected rows
+	 * @return int|false affected rows
 	 */
 	public function markReadTag(int $id = 0, string $idMax = '0', ?FreshRSS_BooleanSearch $filters = null,
 		int $state = 0, bool $is_read = true) {
@@ -630,7 +626,7 @@ SQL;
 			return false;
 		}
 		$affected = $stm->rowCount();
-		if (($affected > 0) && (!$this->updateCacheUnreads(false, false))) {
+		if (($affected > 0) && (!$this->updateCacheUnreads(null, null))) {
 			return false;
 		}
 		return $affected;
@@ -758,7 +754,7 @@ SQL;
 	}
 
 	/** @return array{0:array<int|string>,1:string} */
-	public static function sqlBooleanSearch(string $alias, FreshRSS_BooleanSearch $filters, int $level = 0) {
+	public static function sqlBooleanSearch(string $alias, FreshRSS_BooleanSearch $filters, int $level = 0): array {
 		$search = '';
 		$values = [];
 
diff --git a/app/Models/EntryDAOSQLite.php b/app/Models/EntryDAOSQLite.php
index e509097f2..c86791372 100644
--- a/app/Models/EntryDAOSQLite.php
+++ b/app/Models/EntryDAOSQLite.php
@@ -25,7 +25,7 @@ class FreshRSS_EntryDAOSQLite extends FreshRSS_EntryDAO {
 	/** @param array<string> $errorInfo */
 	protected function autoUpdateDb(array $errorInfo): bool {
 		if ($tableInfo = $this->pdo->query("PRAGMA table_info('entry')")) {
-			$columns = $tableInfo->fetchAll(PDO::FETCH_COLUMN, 1);
+			$columns = $tableInfo->fetchAll(PDO::FETCH_COLUMN, 1) ?: [];
 			foreach (['attributes'] as $column) {
 				if (!in_array($column, $columns)) {
 					return $this->addColumn($column);
@@ -34,14 +34,14 @@ class FreshRSS_EntryDAOSQLite extends FreshRSS_EntryDAO {
 		}
 		if ($tableInfo = $this->pdo->query("SELECT sql FROM sqlite_master where name='tag'")) {
 			$showCreate = $tableInfo->fetchColumn();
-			if (stripos($showCreate, 'tag') === false) {
+			if (is_string($showCreate) && stripos($showCreate, 'tag') === false) {
 				$tagDAO = FreshRSS_Factory::createTagDao();
 				return $tagDAO->createTagTable();	//v1.12.0
 			}
 		}
 		if ($tableInfo = $this->pdo->query("SELECT sql FROM sqlite_master where name='entrytmp'")) {
 			$showCreate = $tableInfo->fetchColumn();
-			if (stripos($showCreate, 'entrytmp') === false) {
+			if (is_string($showCreate) && stripos($showCreate, 'entrytmp') === false) {
 				return $this->createEntryTempTable();	//v1.7.0
 			}
 		}
@@ -78,20 +78,20 @@ DROP TABLE IF EXISTS `tmp`;
 		return $result;
 	}
 
-	protected function updateCacheUnreads($catId = false, $feedId = false) {
+	protected function updateCacheUnreads(?int $catId = null, ?int $feedId = null): bool {
 		$sql = 'UPDATE `_feed` '
 		 . 'SET `cache_nbUnreads`=('
 		 .	'SELECT COUNT(*) AS nbUnreads FROM `_entry` e '
 		 .	'WHERE e.id_feed=`_feed`.id AND e.is_read=0)';
 		$hasWhere = false;
 		$values = array();
-		if ($feedId !== false) {
+		if ($feedId != null) {
 			$sql .= ' WHERE';
 			$hasWhere = true;
 			$sql .= ' id=?';
 			$values[] = $feedId;
 		}
-		if ($catId !== false) {
+		if ($catId != null) {
 			$sql .= $hasWhere ? ' AND' : ' WHERE';
 			$hasWhere = true;
 			$sql .= ' category=?';
@@ -117,8 +117,8 @@ DROP TABLE IF EXISTS `tmp`;
 	 * same if it is an array or not.
 	 *
 	 * @param string|array<string> $ids
-	 * @param boolean $is_read
-	 * @return integer|false affected rows
+	 * @param bool $is_read
+	 * @return int|false affected rows
 	 */
 	public function markRead($ids, bool $is_read = true) {
 		FreshRSS_UserDAO::touch();
@@ -176,9 +176,9 @@ DROP TABLE IF EXISTS `tmp`;
 	 * separated.
 	 *
 	 * @param string $idMax fail safe article ID
-	 * @param boolean $onlyFavorites
-	 * @param integer $priorityMin
-	 * @return integer|false affected rows
+	 * @param bool $onlyFavorites
+	 * @param int $priorityMin
+	 * @return int|false affected rows
 	 */
 	public function markReadEntries(string $idMax = '0', bool $onlyFavorites = false, int $priorityMin = 0,
 		?FreshRSS_BooleanSearch $filters = null, int $state = 0, bool $is_read = true) {
@@ -205,7 +205,7 @@ DROP TABLE IF EXISTS `tmp`;
 			return false;
 		}
 		$affected = $stm->rowCount();
-		if (($affected > 0) && (!$this->updateCacheUnreads(false, false))) {
+		if (($affected > 0) && (!$this->updateCacheUnreads(null, null))) {
 			return false;
 		}
 		return $affected;
@@ -218,9 +218,9 @@ DROP TABLE IF EXISTS `tmp`;
 	 *
 	 * If $idMax equals 0, a deprecated debug message is logged
 	 *
-	 * @param integer $id category ID
+	 * @param int $id category ID
 	 * @param string $idMax fail safe article ID
-	 * @return integer|false affected rows
+	 * @return int|false affected rows
 	 */
 	public function markReadCat(int $id, string $idMax = '0', ?FreshRSS_BooleanSearch $filters = null, int $state = 0, bool $is_read = true) {
 		FreshRSS_UserDAO::touch();
@@ -244,7 +244,7 @@ DROP TABLE IF EXISTS `tmp`;
 			return false;
 		}
 		$affected = $stm->rowCount();
-		if (($affected > 0) && (!$this->updateCacheUnreads($id, false))) {
+		if (($affected > 0) && (!$this->updateCacheUnreads($id, null))) {
 			return false;
 		}
 		return $affected;
@@ -252,9 +252,9 @@ DROP TABLE IF EXISTS `tmp`;
 
 	/**
 	 * Mark all the articles in a tag as read.
-	 * @param integer $id tag ID, or empty for targeting any tag
+	 * @param int $id tag ID, or empty for targeting any tag
 	 * @param string $idMax max article ID
-	 * @return integer|false affected rows
+	 * @return int|false affected rows
 	 */
 	public function markReadTag($id = 0, string $idMax = '0', ?FreshRSS_BooleanSearch $filters = null, int $state = 0, bool $is_read = true) {
 		FreshRSS_UserDAO::touch();
@@ -283,7 +283,7 @@ DROP TABLE IF EXISTS `tmp`;
 			return false;
 		}
 		$affected = $stm->rowCount();
-		if (($affected > 0) && (!$this->updateCacheUnreads(false, false))) {
+		if (($affected > 0) && (!$this->updateCacheUnreads(null, null))) {
 			return false;
 		}
 		return $affected;
diff --git a/app/Models/Factory.php b/app/Models/Factory.php
index 80c611db5..d06c3c63d 100644
--- a/app/Models/Factory.php
+++ b/app/Models/Factory.php
@@ -13,7 +13,7 @@ class FreshRSS_Factory {
 	 * @throws Minz_ConfigurationNamespaceException|Minz_PDOConnectionException
 	 */
 	public static function createCategoryDao(?string $username = null): FreshRSS_CategoryDAO {
-		switch (FreshRSS_Context::$system_conf->db['type']) {
+		switch (FreshRSS_Context::$system_conf->db['type'] ?? '') {
 			case 'sqlite':
 				return new FreshRSS_CategoryDAOSQLite($username);
 			default:
@@ -25,7 +25,7 @@ class FreshRSS_Factory {
 	 * @throws Minz_ConfigurationNamespaceException|Minz_PDOConnectionException
 	 */
 	public static function createFeedDao(?string $username = null): FreshRSS_FeedDAO {
-		switch (FreshRSS_Context::$system_conf->db['type']) {
+		switch (FreshRSS_Context::$system_conf->db['type'] ?? '') {
 			case 'sqlite':
 				return new FreshRSS_FeedDAOSQLite($username);
 			default:
@@ -37,7 +37,7 @@ class FreshRSS_Factory {
 	 * @throws Minz_ConfigurationNamespaceException|Minz_PDOConnectionException
 	 */
 	public static function createEntryDao(?string $username = null): FreshRSS_EntryDAO {
-		switch (FreshRSS_Context::$system_conf->db['type']) {
+		switch (FreshRSS_Context::$system_conf->db['type'] ?? '') {
 			case 'sqlite':
 				return new FreshRSS_EntryDAOSQLite($username);
 			case 'pgsql':
@@ -51,7 +51,7 @@ class FreshRSS_Factory {
 	 * @throws Minz_ConfigurationNamespaceException|Minz_PDOConnectionException
 	 */
 	public static function createTagDao(?string $username = null): FreshRSS_TagDAO {
-		switch (FreshRSS_Context::$system_conf->db['type']) {
+		switch (FreshRSS_Context::$system_conf->db['type'] ?? '') {
 			case 'sqlite':
 				return new FreshRSS_TagDAOSQLite($username);
 			case 'pgsql':
@@ -65,7 +65,7 @@ class FreshRSS_Factory {
 	 * @throws Minz_ConfigurationNamespaceException|Minz_PDOConnectionException
 	 */
 	public static function createStatsDAO(?string $username = null): FreshRSS_StatsDAO {
-		switch (FreshRSS_Context::$system_conf->db['type']) {
+		switch (FreshRSS_Context::$system_conf->db['type'] ?? '') {
 			case 'sqlite':
 				return new FreshRSS_StatsDAOSQLite($username);
 			case 'pgsql':
@@ -79,7 +79,7 @@ class FreshRSS_Factory {
 	 * @throws Minz_ConfigurationNamespaceException|Minz_PDOConnectionException
 	 */
 	public static function createDatabaseDAO(?string $username = null): FreshRSS_DatabaseDAO {
-		switch (FreshRSS_Context::$system_conf->db['type']) {
+		switch (FreshRSS_Context::$system_conf->db['type'] ?? '') {
 			case 'sqlite':
 				return new FreshRSS_DatabaseDAOSQLite($username);
 			case 'pgsql':
diff --git a/app/Models/Feed.php b/app/Models/Feed.php
index 447445d46..ecf875723 100644
--- a/app/Models/Feed.php
+++ b/app/Models/Feed.php
@@ -71,6 +71,7 @@ class FreshRSS_Feed extends Minz_Model {
 	private $error = false;
 	/** @var int */
 	private $ttl = self::TTL_DEFAULT;
+	/** @var array<string,mixed> */
 	private $attributes = [];
 	/** @var bool */
 	private $mute = false;
@@ -93,10 +94,7 @@ class FreshRSS_Feed extends Minz_Model {
 		}
 	}
 
-	/**
-	 * @return FreshRSS_Feed
-	 */
-	public static function example() {
+	public static function example(): FreshRSS_Feed {
 		$f = new FreshRSS_Feed('http://example.net/', false);
 		$f->faviconPrepare();
 		return $f;
@@ -142,12 +140,16 @@ class FreshRSS_Feed extends Minz_Model {
 		return $this->categoryId;
 	}
 
-	public function entries() {
+	/**
+	 * @return array<FreshRSS_Entry>|null
+	 * @deprecated
+	 */
+	public function entries(): ?array {
 		Minz_Log::warning(__method__ . ' is deprecated since FreshRSS 1.16.1!');
 		$simplePie = $this->load(false, true);
 		return $simplePie == null ? [] : iterator_to_array($this->loadEntries($simplePie));
 	}
-	public function name($raw = false): string {
+	public function name(bool $raw = false): string {
 		return $raw || $this->name != '' ? $this->name : preg_replace('%^https?://(www[.])?%i', '', $this->url);
 	}
 	/** @return string HTML-encoded URL of the Web site of the feed */
@@ -167,7 +169,11 @@ class FreshRSS_Feed extends Minz_Model {
 	public function pathEntries(): string {
 		return $this->pathEntries;
 	}
-	public function httpAuth($raw = true) {
+	/**
+	 * @phpstan-return ($raw is true ? string : array{'username':string,'password':string})
+	 * @return array{'username':string,'password':string}|string
+	 */
+	public function httpAuth(bool $raw = true) {
 		if ($raw) {
 			return $this->httpAuth;
 		} else {
@@ -223,7 +229,7 @@ class FreshRSS_Feed extends Minz_Model {
 
 		return $this->nbEntries;
 	}
-	public function nbNotRead($includePending = false): int {
+	public function nbNotRead(bool $includePending = false): int {
 		if ($this->nbNotRead < 0) {
 			$feedDAO = FreshRSS_Factory::createFeedDao();
 			$this->nbNotRead = $feedDAO->countNotRead($this->id());
@@ -231,7 +237,7 @@ class FreshRSS_Feed extends Minz_Model {
 
 		return $this->nbNotRead + ($includePending ? $this->nbPendingNotRead : 0);
 	}
-	public function faviconPrepare() {
+	public function faviconPrepare(): void {
 		require_once(LIB_PATH . '/favicons.php');
 		$url = $this->website;
 		if ($url == '') {
@@ -253,7 +259,7 @@ class FreshRSS_Feed extends Minz_Model {
 			}
 		}
 	}
-	public static function faviconDelete($hash) {
+	public static function faviconDelete(string $hash): void {
 		$path = DATA_PATH . '/favicons/' . $hash;
 		@unlink($path . '.ico');
 		@unlink($path . '.txt');
@@ -262,10 +268,11 @@ class FreshRSS_Feed extends Minz_Model {
 		return Minz_Url::display('/f.php?' . $this->hash());
 	}
 
-	public function _id($value) {
-		$this->id = intval($value);
+	public function _id(int $value): void {
+		$this->id = $value;
 	}
-	public function _url(string $value, bool $validate = true) {
+
+	public function _url(string $value, bool $validate = true): void {
 		$this->hash = '';
 		$url = $value;
 		if ($validate) {
@@ -276,26 +283,26 @@ class FreshRSS_Feed extends Minz_Model {
 		}
 		$this->url = $url;
 	}
-	public function _kind(int $value) {
+
+	public function _kind(int $value): void {
 		$this->kind = $value;
 	}
 
-	/** @param FreshRSS_Category|null $cat */
-	public function _category($cat) {
+	public function _category(?FreshRSS_Category $cat): void {
 		$this->category = $cat;
 		$this->categoryId = $this->category == null ? 0 : $this->category->id();
 	}
 
 	/** @param int|string $id */
-	public function _categoryId($id) {
+	public function _categoryId($id): void {
 		$this->category = null;
 		$this->categoryId = intval($id);
 	}
 
-	public function _name(string $value) {
+	public function _name(string $value): void {
 		$this->name = $value == '' ? '' : trim($value);
 	}
-	public function _website(string $value, bool $validate = true) {
+	public function _website(string $value, bool $validate = true): void {
 		if ($validate) {
 			$value = checkUrl($value);
 		}
@@ -304,37 +311,37 @@ class FreshRSS_Feed extends Minz_Model {
 		}
 		$this->website = $value;
 	}
-	public function _description(string $value) {
+	public function _description(string $value): void {
 		$this->description = $value == '' ? '' : $value;
 	}
-	public function _lastUpdate($value) {
-		$this->lastUpdate = intval($value);
+	public function _lastUpdate(int $value): void {
+		$this->lastUpdate = $value;
 	}
-	public function _priority($value) {
-		$this->priority = intval($value);
+	public function _priority(int $value): void {
+		$this->priority = $value;
 	}
 	/** @param string $value HTML-encoded CSS selector */
-	public function _pathEntries(string $value) {
+	public function _pathEntries(string $value): void {
 		$this->pathEntries = $value;
 	}
-	public function _httpAuth(string $value) {
+	public function _httpAuth(string $value): void {
 		$this->httpAuth = $value;
 	}
-	public function _error($value) {
+	/** @param bool|int $value */
+	public function _error($value): void {
 		$this->error = (bool)$value;
 	}
-	public function _mute(bool $value) {
+	public function _mute(bool $value): void {
 		$this->mute = $value;
 	}
-	public function _ttl($value) {
-		$value = intval($value);
+	public function _ttl(int $value): void {
 		$value = min($value, 100000000);
 		$this->ttl = abs($value);
 		$this->mute = $value < self::TTL_DEFAULT;
 	}
 
 	/** @param string|array<mixed>|bool|int|null $value Value, not HTML-encoded */
-	public function _attributes(string $key, $value) {
+	public function _attributes(string $key, $value): void {
 		if ($key == '') {
 			if (is_string($value)) {
 				$value = json_decode($value, true);
@@ -349,17 +356,14 @@ class FreshRSS_Feed extends Minz_Model {
 		}
 	}
 
-	public function _nbNotRead($value) {
-		$this->nbNotRead = intval($value);
+	public function _nbNotRead(int $value): void {
+		$this->nbNotRead = $value;
 	}
-	public function _nbEntries($value) {
-		$this->nbEntries = intval($value);
+	public function _nbEntries(int $value): void {
+		$this->nbEntries = $value;
 	}
 
-	/**
-	 * @return SimplePie|null
-	 */
-	public function load(bool $loadDetails = false, bool $noCache = false) {
+	public function load(bool $loadDetails = false, bool $noCache = false): ?SimplePie {
 		if ($this->url != '') {
 			// @phpstan-ignore-next-line
 			if (CACHE_PATH === false) {
@@ -440,7 +444,7 @@ class FreshRSS_Feed extends Minz_Model {
 	/**
 	 * @return array<string>
 	 */
-	public function loadGuids(SimplePie $simplePie) {
+	public function loadGuids(SimplePie $simplePie): array {
 		$hasUniqueGuids = true;
 		$testGuids = [];
 		$guids = [];
@@ -474,6 +478,9 @@ class FreshRSS_Feed extends Minz_Model {
 		return $guids;
 	}
 
+	/**
+	 * @return iterable<FreshRSS_Entry>
+	 */
 	public function loadEntries(SimplePie $simplePie) {
 		$hasBadGuids = $this->attributes('hasBadGuids');
 
@@ -591,10 +598,7 @@ class FreshRSS_Feed extends Minz_Model {
 		}
 	}
 
-	/**
-	 * @return SimplePie|null
-	 */
-	public function loadHtmlXpath() {
+	public function loadHtmlXpath(): ?SimplePie {
 		if ($this->url == '') {
 			return null;
 		}
@@ -708,7 +712,7 @@ class FreshRSS_Feed extends Minz_Model {
 				if ($item['title'] != '' || $item['content'] != '' || $item['link'] != '') {
 					// HTML-encoding/escaping of the relevant fields (all except 'content')
 					foreach (['author', 'categories', 'guid', 'link', 'thumbnail', 'timestamp', 'title'] as $key) {
-						if (!empty($item[$key])) {
+						if (!empty($item[$key]) && is_string($item[$key])) {
 							$item[$key] = Minz_Helper::htmlspecialchars_utf8($item[$key]);
 						}
 					}
@@ -731,7 +735,7 @@ class FreshRSS_Feed extends Minz_Model {
 	/**
 	 * To keep track of some new potentially unread articles since last commit+fetch from database
 	 */
-	public function incPendingUnread(int $n = 1) {
+	public function incPendingUnread(int $n = 1): void {
 		$this->nbPendingNotRead += $n;
 	}
 
@@ -770,6 +774,7 @@ class FreshRSS_Feed extends Minz_Model {
 
 	/**
 	 * Remember to call updateCachedValue($id_feed) or updateCachedValues() just after
+	 * @return int|false
 	 */
 	public function cleanOldEntries() {
 		$archiving = $this->attributes('archiving');
@@ -785,7 +790,6 @@ class FreshRSS_Feed extends Minz_Model {
 			$entryDAO = FreshRSS_Factory::createEntryDao();
 			$nb = $entryDAO->cleanOldEntries($this->id(), $archiving);
 			if ($nb > 0) {
-				$needFeedCacheRefresh = true;
 				Minz_Log::debug($nb . ' entries cleaned in feed [' . $this->url(false) . '] with: ' . json_encode($archiving));
 			}
 			return $nb;
@@ -793,6 +797,7 @@ class FreshRSS_Feed extends Minz_Model {
 		return false;
 	}
 
+	/** @param array<string,mixed> $attributes */
 	public static function cacheFilename(string $url, array $attributes, int $kind = FreshRSS_Feed::KIND_RSS): string {
 		$simplePie = customSimplePie($attributes);
 		$filename = $simplePie->get_cache_filename($url);
@@ -851,12 +856,12 @@ class FreshRSS_Feed extends Minz_Model {
 	}
 
 	/**
-	 * @param array<FreshRSS_FilterAction> $filterActions
+	 * @param array<FreshRSS_FilterAction>|null $filterActions
 	 */
-	private function _filterActions($filterActions) {
+	private function _filterActions(?array $filterActions): void {
 		$this->filterActions = $filterActions;
 		if (is_array($this->filterActions) && !empty($this->filterActions)) {
-			$this->_attributes('filters', array_map(function ($af) {
+			$this->_attributes('filters', array_map(static function (?FreshRSS_FilterAction $af) {
 					return $af == null ? null : $af->toJSON();
 				}, $this->filterActions));
 		} else {
@@ -885,10 +890,10 @@ class FreshRSS_Feed extends Minz_Model {
 	/**
 	 * @param array<string> $filters
 	 */
-	public function _filtersAction(string $action, $filters) {
+	public function _filtersAction(string $action, array $filters): void {
 		$action = trim($action);
 		if ($action == '' || !is_array($filters)) {
-			return false;
+			return;
 		}
 		$filters = array_unique(array_map('trim', $filters));
 		$filterActions = $this->filterActions();
diff --git a/app/Models/FeedDAO.php b/app/Models/FeedDAO.php
index 9138f3d59..837fef7f1 100644
--- a/app/Models/FeedDAO.php
+++ b/app/Models/FeedDAO.php
@@ -268,7 +268,7 @@ class FreshRSS_FeedDAO extends Minz_ModelPdo {
 	 * @param bool|null $muted to include only muted feeds
 	 * @return int|false
 	 */
-	public function deleteFeedByCategory(int $id, $muted = null) {
+	public function deleteFeedByCategory(int $id, ?bool $muted = null) {
 		$sql = 'DELETE FROM `_feed` WHERE category=?';
 		if ($muted) {
 			$sql .= ' AND ttl < 0';
@@ -338,7 +338,7 @@ SQL;
 	}
 
 	/** @return array<string,string> */
-	public function listFeedsNewestItemUsec(?int $id_feed = null) {
+	public function listFeedsNewestItemUsec(?int $id_feed = null): array {
 		$sql = 'SELECT id_feed, MAX(id) as newest_item_us FROM `_entry` ';
 		if ($id_feed === null) {
 			$sql .= 'GROUP BY id_feed';
@@ -358,7 +358,7 @@ SQL;
 	 * Use $defaultCacheDuration == -1 to return all feeds, without filtering them by TTL.
 	 * @return array<FreshRSS_Feed>
 	 */
-	public function listFeedsOrderUpdate(int $defaultCacheDuration = 3600, int $limit = 0) {
+	public function listFeedsOrderUpdate(int $defaultCacheDuration = 3600, int $limit = 0): array {
 		$this->updateTTL();
 		$sql = 'SELECT id, url, kind, name, website, `lastUpdate`, `pathEntries`, `httpAuth`, ttl, attributes '
 			. 'FROM `_feed` '
@@ -398,7 +398,7 @@ SQL;
 	 * @param bool|null $muted to include only muted feeds
 	 * @return array<FreshRSS_Feed>
 	 */
-	public function listByCategory(int $cat, $muted = null): array {
+	public function listByCategory(int $cat, ?bool $muted = null): array {
 		$sql = 'SELECT * FROM `_feed` WHERE category=?';
 		if ($muted) {
 			$sql .= ' AND ttl < 0';
diff --git a/app/Models/Search.php b/app/Models/Search.php
index 14d77cb6f..f5b061512 100644
--- a/app/Models/Search.php
+++ b/app/Models/Search.php
@@ -234,11 +234,11 @@ class FreshRSS_Search {
 	}
 
 	/**
-	 * @param array<string> $anArray
+	 * @param array<string>|null $anArray
 	 * @return array<string>
 	 */
-	private static function removeEmptyValues($anArray): array {
-		return empty($anArray) ? [] : array_filter($anArray, function($value) { return $value !== ''; });
+	private static function removeEmptyValues(?array $anArray): array {
+		return empty($anArray) ? [] : array_filter($anArray, static function(string $value) { return $value !== ''; });
 	}
 
 	/**
diff --git a/app/Models/Share.php b/app/Models/Share.php
index 7bd6de9cf..b01d285f3 100644
--- a/app/Models/Share.php
+++ b/app/Models/Share.php
@@ -49,7 +49,7 @@ class FreshRSS_Share {
 			self::register($share_options);
 		}
 
-		uasort(self::$list_sharing, function ($a, $b) {
+		uasort(self::$list_sharing, static function (FreshRSS_Share $a, FreshRSS_Share $b) {
 			return strcasecmp($a->name(), $b->name());
 		});
 	}
@@ -303,7 +303,7 @@ class FreshRSS_Share {
 	 * @param array<string> $transform an array containing a list of functions to apply.
 	 * @return string the transformed data.
 	 */
-	private static function transform(string $data, $transform): string {
+	private static function transform(string $data, array $transform): string {
 		if (!is_array($transform) || empty($transform)) {
 			return $data;
 		}
diff --git a/app/Models/StatsDAO.php b/app/Models/StatsDAO.php
index 30d7aa2ef..a0a4ec498 100644
--- a/app/Models/StatsDAO.php
+++ b/app/Models/StatsDAO.php
@@ -13,7 +13,7 @@ class FreshRSS_StatsDAO extends Minz_ModelPdo {
 	 *
 	 * @return array{'main_stream':array{'total':int,'count_unreads':int,'count_reads':int,'count_favorites':int},'all_feeds':array{'total':int,'count_unreads':int,'count_reads':int,'count_favorites':int}}
 	 */
-	public function calculateEntryRepartition() {
+	public function calculateEntryRepartition(): array {
 		return array(
 			'main_stream' => $this->calculateEntryRepartitionPerFeed(null, true),
 			'all_feeds' => $this->calculateEntryRepartitionPerFeed(null, false),
@@ -57,7 +57,7 @@ SQL;
 	 * Calculates entry count per day on a 30 days period.
 	 * @return array<int,int>
 	 */
-	public function calculateEntryCount() {
+	public function calculateEntryCount(): array {
 		$count = $this->initEntryCountArray();
 		$midnight = mktime(0, 0, 0);
 		$oldest = $midnight - (self::ENTRY_COUNT_PERIOD * 86400);
@@ -87,7 +87,7 @@ SQL;
 	 * Initialize an array for the entry count.
 	 * @return array<int,int>
 	 */
-	protected function initEntryCountArray() {
+	protected function initEntryCountArray(): array {
 		return $this->initStatsArray(-self::ENTRY_COUNT_PERIOD, -1);
 	}
 
@@ -348,8 +348,8 @@ SQL;
 	 * @param array<string> $data
 	 * @return array<string>
 	 */
-	private function convertToTranslatedJson(array $data = array()) {
-		$translated = array_map(function($a) {
+	private function convertToTranslatedJson(array $data = array()): array {
+		$translated = array_map(static function (string $a) {
 			return _t('gen.date.' . $a);
 		}, $data);
 
diff --git a/app/Models/StatsDAOPGSQL.php b/app/Models/StatsDAOPGSQL.php
index 9548027ce..52a99d2f4 100644
--- a/app/Models/StatsDAOPGSQL.php
+++ b/app/Models/StatsDAOPGSQL.php
@@ -5,7 +5,7 @@ class FreshRSS_StatsDAOPGSQL extends FreshRSS_StatsDAO {
 	/**
 	 * Calculates the number of article per hour of the day per feed
 	 *
-	 * @param integer $feed id
+	 * @param int $feed id
 	 * @return array<int,int>
 	 */
 	public function calculateEntryRepartitionPerFeedPerHour(?int $feed = null): array {
@@ -48,6 +48,9 @@ ORDER BY period ASC
 SQL;
 
 		$stm = $this->pdo->query($sql);
+		if ($stm === false) {
+			return [];
+		}
 		$res = $stm->fetchAll(PDO::FETCH_NAMED);
 
 		switch ($period) {
diff --git a/app/Models/StatsDAOSQLite.php b/app/Models/StatsDAOSQLite.php
index 632fa17e2..9f292aae6 100644
--- a/app/Models/StatsDAOSQLite.php
+++ b/app/Models/StatsDAOSQLite.php
@@ -25,6 +25,9 @@ ORDER BY period ASC
 SQL;
 
 		$stm = $this->pdo->query($sql);
+		if ($stm === false) {
+			return [];
+		}
 		$res = $stm->fetchAll(PDO::FETCH_NAMED);
 
 		switch ($period) {
diff --git a/app/Models/Tag.php b/app/Models/Tag.php
index d88f0c1c2..4ab28a286 100644
--- a/app/Models/Tag.php
+++ b/app/Models/Tag.php
@@ -97,7 +97,7 @@ class FreshRSS_Tag extends Minz_Model {
 	}
 
 	/**
-	 * @param string|int$value
+	 * @param string|int $value
 	 */
 	public function _nbUnread($value): void {
 		$this->nbUnread = (int)$value;
diff --git a/app/Models/TagDAO.php b/app/Models/TagDAO.php
index c27a69f11..0f491e706 100644
--- a/app/Models/TagDAO.php
+++ b/app/Models/TagDAO.php
@@ -245,7 +245,7 @@ SQL;
 	}
 
 	/** @return array<string,string> */
-	public function listTagsNewestItemUsec(?int $id_tag = null) {
+	public function listTagsNewestItemUsec(?int $id_tag = null): array {
 		$sql = 'SELECT t.id AS id_tag, MAX(e.id) AS newest_item_us '
 			 . 'FROM `_tag` t '
 			 . 'LEFT OUTER JOIN `_entrytag` et ON et.id_tag = t.id '
@@ -440,7 +440,7 @@ SQL;
 	 * @param array<array<string,string|int>>|array<string,string|int> $listDAO
 	 * @return array<FreshRSS_Tag>
 	 */
-	private static function daoToTag(array $listDAO) {
+	private static function daoToTag(array $listDAO): array {
 		$list = array();
 		if (!is_array($listDAO)) {
 			$listDAO = array($listDAO);
diff --git a/app/Models/TagDAOSQLite.php b/app/Models/TagDAOSQLite.php
index 910455546..50683cf84 100644
--- a/app/Models/TagDAOSQLite.php
+++ b/app/Models/TagDAOSQLite.php
@@ -10,7 +10,7 @@ class FreshRSS_TagDAOSQLite extends FreshRSS_TagDAO {
 	protected function autoUpdateDb(array $errorInfo): bool {
 		if ($tableInfo = $this->pdo->query("SELECT sql FROM sqlite_master where name='tag'")) {
 			$showCreate = $tableInfo->fetchColumn();
-			if (stripos($showCreate, 'tag') === false) {
+			if (is_string($showCreate) && stripos($showCreate, 'tag') === false) {
 				return $this->createTagTable();	//v1.12.0
 			}
 		}
diff --git a/app/Models/UserQuery.php b/app/Models/UserQuery.php
index 278074362..f0d809378 100644
--- a/app/Models/UserQuery.php
+++ b/app/Models/UserQuery.php
@@ -34,7 +34,7 @@ class FreshRSS_UserQuery {
 	private $tag_dao;
 
 	/**
-	 * @param array<string,string> $query
+	 * @param array<string,string|int> $query
 	 */
 	public function __construct(array $query, FreshRSS_FeedDAO $feed_dao = null, FreshRSS_CategoryDAO $category_dao = null, FreshRSS_TagDAO $tag_dao = null) {
 		$this->category_dao = $category_dao;
diff --git a/app/Models/View.php b/app/Models/View.php
index e908bdfad..87302a4e1 100644
--- a/app/Models/View.php
+++ b/app/Models/View.php
@@ -57,7 +57,7 @@ class FreshRSS_View extends Minz_View {
 	public $show_email_field;
 	/** @var string */
 	public $username;
-	/** @var array<array{'last_user_activity':int, 'language':string,'enabled':bool,'is_admin':bool, 'enabled':bool, 'article_count':int, 'database_size':int, 'last_user_activity', 'mail_login':string, 'feed_count':int, 'is_default':bool}>  */
+	/** @var array<array{'last_user_activity':int,'language':string,'enabled':bool,'is_admin':bool,'enabled':bool,'article_count':int,'database_size':int,'last_user_activity','mail_login':string,'feed_count':int,'is_default':bool}> */
 	public $users;
 
 	// Updates
@@ -73,7 +73,7 @@ class FreshRSS_View extends Minz_View {
 	public $status_database;
 
 	// Archiving
-	/** @var int|false */
+	/** @var int */
 	public $nb_total;
 	/** @var int */
 	public $size_total;
diff --git a/app/Services/ExportService.php b/app/Services/ExportService.php
index fd5d48f72..10d5ca2cc 100644
--- a/app/Services/ExportService.php
+++ b/app/Services/ExportService.php
@@ -87,8 +87,8 @@ class FreshRSS_Export_Service {
 
 	/**
 	 * Generate the entries file content for the given feed.
-	 * @param integer $feed_id
-	 * @param integer $max_number_entries
+	 * @param int $feed_id
+	 * @param int $max_number_entries
 	 * @return array{0:string,1:string}|null First item is the filename, second item is the content.
 	 *                    It also can return null if the feed doesn’t exist.
 	 */
diff --git a/app/Services/ImportService.php b/app/Services/ImportService.php
index 6f6ca13ac..3707e4c5e 100644
--- a/app/Services/ImportService.php
+++ b/app/Services/ImportService.php
@@ -15,10 +15,8 @@ class FreshRSS_Import_Service {
 
 	/**
 	 * Initialize the service for the given user.
-	 *
-	 * @param string $username
 	 */
-	public function __construct($username = null) {
+	public function __construct(?string $username = null) {
 		$this->catDAO = FreshRSS_Factory::createCategoryDao($username);
 		$this->feedDAO = FreshRSS_Factory::createFeedDao($username);
 	}
@@ -33,9 +31,9 @@ class FreshRSS_Import_Service {
 	 *
 	 * @param string $opml_file the OPML file content.
 	 * @param FreshRSS_Category|null $forced_category force the feeds to be associated to this category.
-	 * @param boolean $dry_run true to not create categories and feeds in database.
+	 * @param bool $dry_run true to not create categories and feeds in database.
 	 */
-	public function importOpml(string $opml_file, $forced_category = null, $dry_run = false) {
+	public function importOpml(string $opml_file, ?FreshRSS_Category $forced_category = null, bool $dry_run = false): void {
 		@set_time_limit(300);
 		$this->lastStatus = true;
 		$opml_array = array();
@@ -132,20 +130,17 @@ class FreshRSS_Import_Service {
 				}
 			}
 		}
-
-		return;
 	}
 
 	/**
 	 * Create a feed from a feed element (i.e. OPML outline).
 	 *
-	 * @param array<string, string> $feed_elt An OPML element (must be a feed element).
+	 * @param array<string,string> $feed_elt An OPML element (must be a feed element).
 	 * @param FreshRSS_Category $category The category to associate to the feed.
-	 * @param boolean $dry_run true to not create the feed in database.
-	 *
+	 * @param bool $dry_run true to not create the feed in database.
 	 * @return FreshRSS_Feed|null The created feed, or null if it failed.
 	 */
-	private function createFeed($feed_elt, $category, $dry_run) {
+	private function createFeed(array $feed_elt, FreshRSS_Category $category, bool $dry_run): ?FreshRSS_Feed {
 		$url = Minz_Helper::htmlspecialchars_utf8($feed_elt['xmlUrl']);
 		$name = $feed_elt['text'] ?? $feed_elt['title'] ?? '';
 		$name = Minz_Helper::htmlspecialchars_utf8($name);
@@ -256,12 +251,11 @@ class FreshRSS_Import_Service {
 	/**
 	 * Create and return a category.
 	 *
-	 * @param array<string, string> $category_element An OPML element (must be a category element).
-	 * @param boolean $dry_run true to not create the category in database.
-	 *
+	 * @param array<string,string> $category_element An OPML element (must be a category element).
+	 * @param bool $dry_run true to not create the category in database.
 	 * @return FreshRSS_Category|null The created category, or null if it failed.
 	 */
-	private function createCategory($category_element, $dry_run) {
+	private function createCategory(array $category_element, bool $dry_run): ?FreshRSS_Category {
 		$name = $category_element['text'] ?? $category_element['title'] ?? '';
 		$name = Minz_Helper::htmlspecialchars_utf8($name);
 		$category = new FreshRSS_Category($name);
@@ -295,14 +289,13 @@ class FreshRSS_Import_Service {
 	 * This method is applied to a list of outlines. It merges the different
 	 * list of feeds from several outlines into one array.
 	 *
-	 * @param array $outlines
+	 * @param array<mixed> $outlines
 	 *     The outlines from which to extract the outlines.
 	 * @param string $parent_category_name
 	 *     The name of the parent category of the current outlines.
-	 *
-	 * @return array[]
+	 * @return array{0:array<mixed>,1:array<mixed>}
 	 */
-	private function loadFromOutlines($outlines, $parent_category_name) {
+	private function loadFromOutlines(array $outlines, string $parent_category_name): array {
 		$categories_elements = [];
 		$categories_to_feeds = [];
 
@@ -342,14 +335,14 @@ class FreshRSS_Import_Service {
 	 * exists), it will add the outline to an array accessible by its category
 	 * name.
 	 *
-	 * @param array $outline
+	 * @param array<mixed> $outline
 	 *     The outline from which to extract the categories and feeds outlines.
 	 * @param string $parent_category_name
 	 *     The name of the parent category of the current outline.
 	 *
-	 * @return array[]
+	 * @return array{0:array<string,mixed>,1:array<string,mixed>}
 	 */
-	private function loadFromOutline($outline, $parent_category_name) {
+	private function loadFromOutline($outline, $parent_category_name): array {
 		$categories_elements = [];
 		$categories_to_feeds = [];
 
@@ -396,7 +389,7 @@ class FreshRSS_Import_Service {
 		return [$categories_elements, $categories_to_feeds];
 	}
 
-	private static function log($message) {
+	private static function log(string $message): void {
 		if (FreshRSS_Context::$isCli) {
 			fwrite(STDERR, "FreshRSS error during OPML import: {$message}\n");
 		} else {
diff --git a/app/Utils/feverUtil.php b/app/Utils/feverUtil.php
index 0e4b712ce..4de321732 100644
--- a/app/Utils/feverUtil.php
+++ b/app/Utils/feverUtil.php
@@ -57,7 +57,7 @@ class FreshRSS_fever_Util {
 	 *
 	 * @return bool true if the deletion succeeded, else false.
 	 */
-	public static function deleteKey(string $username) {
+	public static function deleteKey(string $username): bool {
 		$userConfig = get_user_configuration($username);
 		if ($userConfig === null) {
 			return false;
diff --git a/app/actualize_script.php b/app/actualize_script.php
index 4a38c13f7..160911f53 100755
--- a/app/actualize_script.php
+++ b/app/actualize_script.php
@@ -54,7 +54,7 @@ if (($handle = @fopen($mutexFile, 'x')) === false) {
 }
 fclose($handle);
 
-register_shutdown_function(function () use ($mutexFile) {
+register_shutdown_function(static function () use ($mutexFile) {
 	unlink($mutexFile);
 });
 // </Mutex>
@@ -63,7 +63,7 @@ notice('FreshRSS starting feeds actualization at ' . $begin_date->format('c'));
 
 // make sure the PHP setup of the CLI environment is compatible with FreshRSS as well
 echo 'Failed requirements!', "\n";
-performRequirementCheck(FreshRSS_Context::$system_conf->db['type']);
+performRequirementCheck(FreshRSS_Context::$system_conf->db['type'] ?? '');
 ob_clean();
 
 echo 'Results: ', "\n";	//Buffered
@@ -100,7 +100,7 @@ foreach ($users as $user) {
 	// NB: Extensions and hooks are reinitialised there
 	$app->init();
 
-	Minz_ExtensionManager::addHook('feed_before_actualize', function ($feed) use ($mutexFile) {
+	Minz_ExtensionManager::addHook('feed_before_actualize', static function (FreshRSS_Feed $feed) use ($mutexFile) {
 		touch($mutexFile);
 		return $feed;
 	});
diff --git a/app/install.php b/app/install.php
index b43aa81bb..599fd9863 100644
--- a/app/install.php
+++ b/app/install.php
@@ -18,7 +18,11 @@ if (STEP === 2 && isset($_POST['type'])) {
 	Minz_Session::_param('bd_type', $_POST['type']);
 }
 
-function param($key, $default = false) {
+/**
+ * @param mixed $default
+ * @return mixed
+ */
+function param(string $key, $default = false) {
 	if (isset($_POST[$key])) {
 		return $_POST[$key];
 	} else {
@@ -27,7 +31,7 @@ function param($key, $default = false) {
 }
 
 // gestion internationalisation
-function initTranslate() {
+function initTranslate(): void {
 	Minz_Translate::init();
 	$available_languages = Minz_Translate::availableLanguages();
 
@@ -42,14 +46,14 @@ function initTranslate() {
 	Minz_Translate::reset(Minz_Session::param('language'));
 }
 
-function get_best_language() {
+function get_best_language(): string {
 	$accept = empty($_SERVER['HTTP_ACCEPT_LANGUAGE']) ? '' : $_SERVER['HTTP_ACCEPT_LANGUAGE'];
 	return strtolower(substr($accept, 0, 2));
 }
 
 
 /*** SAUVEGARDES ***/
-function saveLanguage() {
+function saveLanguage(): bool {
 	if (!empty($_POST)) {
 		if (!isset($_POST['language'])) {
 			return false;
@@ -60,9 +64,10 @@ function saveLanguage() {
 
 		header('Location: index.php?step=1');
 	}
+	return true;
 }
 
-function saveStep1() {
+function saveStep1(): void {
 	if (isset($_POST['freshrss-keep-install']) &&
 			$_POST['freshrss-keep-install'] === '1') {
 		// We want to keep our previous installation of FreshRSS
@@ -79,12 +84,12 @@ function saveStep1() {
 				'auth_type' => FreshRSS_Context::$system_conf->auth_type,
 				'default_user' => Minz_User::name(),
 				'passwordHash' => FreshRSS_Context::$user_conf->passwordHash,
-				'bd_type' => FreshRSS_Context::$system_conf->db['type'],
-				'bd_host' => FreshRSS_Context::$system_conf->db['host'],
-				'bd_user' => FreshRSS_Context::$system_conf->db['user'],
-				'bd_password' => FreshRSS_Context::$system_conf->db['password'],
-				'bd_base' => FreshRSS_Context::$system_conf->db['base'],
-				'bd_prefix' => FreshRSS_Context::$system_conf->db['prefix'],
+				'bd_type' => FreshRSS_Context::$system_conf->db['type'] ?? '',
+				'bd_host' => FreshRSS_Context::$system_conf->db['host'] ?? '',
+				'bd_user' => FreshRSS_Context::$system_conf->db['user'] ?? '',
+				'bd_password' => FreshRSS_Context::$system_conf->db['password'] ?? '',
+				'bd_base' => FreshRSS_Context::$system_conf->db['base'] ?? '',
+				'bd_prefix' => FreshRSS_Context::$system_conf->db['prefix'] ?? '',
 				'bd_error' => false,
 			]);
 
@@ -92,7 +97,7 @@ function saveStep1() {
 	}
 }
 
-function saveStep2() {
+function saveStep2(): void {
 	if (!empty($_POST)) {
 		if (Minz_Session::param('bd_type') === 'sqlite') {
 			Minz_Session::_params([
@@ -190,9 +195,9 @@ function saveStep2() {
 	invalidateHttpCache();
 }
 
-function saveStep3() {
+function saveStep3(): bool {
 	if (!empty($_POST)) {
-		$system_default_config = Minz_Configuration::get('default_system');
+		$system_default_config = FreshRSS_SystemConfiguration::get('default_system');
 		Minz_Session::_params([
 				'title' => $system_default_config->title,
 				'auth_type' => param('auth_type', 'form'),
@@ -242,10 +247,11 @@ function saveStep3() {
 
 		header('Location: index.php?step=4');
 	}
+	return true;
 }
 
 /*** VÉRIFICATIONS ***/
-function checkStep() {
+function checkStep(): void {
 	$s0 = checkStep0();
 	$s1 = checkRequirements();
 	$s2 = checkStep2();
@@ -262,7 +268,8 @@ function checkStep() {
 	Minz_Session::_param('actualize_feeds', true);
 }
 
-function checkStep0() {
+/** @return array<string,string> */
+function checkStep0(): array {
 	$languages = Minz_Translate::availableLanguages();
 	$language = Minz_Session::param('language') != '' && in_array(Minz_Session::param('language'), $languages);
 	$sessionWorking = Minz_Session::param('sessionWorking') === 'ok';
@@ -274,7 +281,7 @@ function checkStep0() {
 	);
 }
 
-function freshrss_already_installed() {
+function freshrss_already_installed(): bool {
 	$conf_path = join_path(DATA_PATH, 'config.php');
 	if (!file_exists($conf_path)) {
 		return false;
@@ -300,7 +307,8 @@ function freshrss_already_installed() {
 	return true;
 }
 
-function checkStep2() {
+/** @return array<string,string> */
+function checkStep2(): array {
 	$conf = is_writable(join_path(DATA_PATH, 'config.php'));
 
 	$bd = Minz_Session::param('bd_type') != '';
@@ -314,7 +322,8 @@ function checkStep2() {
 	];
 }
 
-function checkStep3() {
+/** @return array<string,string> */
+function checkStep3(): array {
 	$conf = Minz_Session::param('default_user') != '';
 
 	$form = Minz_Session::param('auth_type') != '';
@@ -335,7 +344,7 @@ function checkStep3() {
 
 
 /*** AFFICHAGE ***/
-function printStep0() {
+function printStep0(): void {
 	$actual = Minz_Translate::language();
 	$languages = Minz_Translate::availableLanguages();
 	$s0 = checkStep0();
@@ -373,7 +382,8 @@ function printStep0() {
 <?php
 }
 
-function printStep1Template($key, $value, $messageParams = []) {
+/** @param array<string> $messageParams */
+function printStep1Template(string $key, string $value, array $messageParams = []): void {
 	if ('ok' === $value) {
 		$message = _t("install.check.{$key}.ok", ...$messageParams);
 		?><p class="alert alert-success"><span class="alert-head"><?= _t('gen.short.ok') ?></span> <?= $message ?></p><?php
@@ -383,10 +393,12 @@ function printStep1Template($key, $value, $messageParams = []) {
 	}
 }
 
-function getProcessUsername() {
+function getProcessUsername(): string {
 	if (function_exists('posix_getpwuid') && function_exists('posix_geteuid')) {
-		$processUser = posix_getpwuid(posix_geteuid());
-		return $processUser['name'];
+		$processUser = posix_getpwuid(posix_geteuid()) ?: [];
+		if (!empty($processUser['name'])) {
+			return $processUser['name'];
+		}
 	}
 
 	if (function_exists('exec')) {
@@ -400,7 +412,7 @@ function getProcessUsername() {
 }
 
 // @todo refactor this view with the check_install action
-function printStep1() {
+function printStep1(): void {
 	$res = checkRequirements();
 	$processUsername = getProcessUsername();
 ?>
@@ -408,14 +420,10 @@ function printStep1() {
 	<noscript><p class="alert alert-warn"><span class="alert-head"><?= _t('gen.short.attention') ?></span> <?= _t('install.javascript_is_better') ?></p></noscript>
 
 	<?php
-	if (function_exists('curl_version')) {
-		$version = curl_version();
-	} else {
-		$version['version'] = '';
-	}
+	$version = function_exists('curl_version') ? curl_version() : [];
 	printStep1Template('php', $res['php'], [PHP_VERSION, FRESHRSS_MIN_PHP_VERSION]);
 	printStep1Template('pdo', $res['pdo']);
-	printStep1Template('curl', $res['curl'], [$version['version']]);
+	printStep1Template('curl', $res['curl'], [$version['version'] ?? '']);
 	printStep1Template('json', $res['json']);
 	printStep1Template('pcre', $res['pcre']);
 	printStep1Template('ctype', $res['ctype']);
@@ -466,8 +474,8 @@ function printStep1() {
 <?php
 }
 
-function printStep2() {
-	$system_default_config = Minz_Configuration::get('default_system');
+function printStep2(): void {
+	$system_default_config = FreshRSS_SystemConfiguration::get('default_system');
 	$s2 = checkStep2();
 	if ($s2['all'] == 'ok') { ?>
 	<p class="alert alert-success"><span class="alert-head"><?= _t('gen.short.ok') ?></span> <?= _t('install.bdd.conf.ok') ?></p>
@@ -509,7 +517,7 @@ function printStep2() {
 			<label class="group-name" for="host"><?= _t('install.bdd.host') ?></label>
 			<div class="group-controls">
 				<input type="text" id="host" name="host" pattern="[0-9A-Z/a-z_.-]{1,64}(:[0-9]{2,5})?" value="<?=
-					isset($_SESSION['bd_host']) ? $_SESSION['bd_host'] : $system_default_config->db['host'] ?>" tabindex="2" />
+					isset($_SESSION['bd_host']) ? $_SESSION['bd_host'] : ($system_default_config->db['host'] ?? '') ?>" tabindex="2" />
 			</div>
 		</div>
 
@@ -544,7 +552,7 @@ function printStep2() {
 			<label class="group-name" for="prefix"><?= _t('install.bdd.prefix') ?></label>
 			<div class="group-controls">
 				<input type="text" id="prefix" name="prefix" maxlength="16" pattern="[0-9A-Za-z_]{1,16}" value="<?=
-					isset($_SESSION['bd_prefix']) ? $_SESSION['bd_prefix'] : $system_default_config->db['prefix'] ?>" tabindex="7" />
+					isset($_SESSION['bd_prefix']) ? $_SESSION['bd_prefix'] : ($system_default_config->db['prefix'] ?? '') ?>" tabindex="7" />
 			</div>
 		</div>
 		</div>
@@ -562,11 +570,11 @@ function printStep2() {
 <?php
 }
 
-function no_auth($auth_type) {
+function no_auth(string $auth_type): bool {
 	return !in_array($auth_type, array('form', 'http_auth', 'none'));
 }
 
-function printStep3() {
+function printStep3(): void {
 	$auth_type = isset($_SESSION['auth_type']) ? $_SESSION['auth_type'] : '';
 	$s3 = checkStep3();
 	if ($s3['all'] == 'ok') { ?>
@@ -628,7 +636,7 @@ function printStep3() {
 <?php
 }
 
-function printStep4() {
+function printStep4(): void {
 ?>
 	<p class="alert alert-success"><span class="alert-head"><?= _t('install.congratulations') ?></span> <?= _t('install.ok') ?></p>
 	<div class="form-group form-actions">
@@ -639,7 +647,7 @@ function printStep4() {
 <?php
 }
 
-function printStep5() {
+function printStep5(): void {
 ?>
 	<p class="alert alert-error">
 		<span class="alert-head"><?= _t('gen.short.damn') ?></span>
@@ -676,7 +684,7 @@ case 5:
 }
 ?>
 <!DOCTYPE html>
-<html<?php
+<html <?php
 if (_t('gen.dir') === 'rtl') {
 	echo ' dir="rtl" class="rtl"';
 }
diff --git a/app/views/helpers/export/articles.phtml b/app/views/helpers/export/articles.phtml
index cc6a62377..60041339b 100644
--- a/app/views/helpers/export/articles.phtml
+++ b/app/views/helpers/export/articles.phtml
@@ -11,7 +11,7 @@ $articles = array(
 	'items' => array(),
 );
 
-echo rtrim(json_encode($articles, $options), " ]}\n\r\t"), "\n";
+echo rtrim(json_encode($articles, $options) ?: '', " ]}\n\r\t"), "\n";
 $first = true;
 
 if (empty($this->entryIdsTagNames)) {
diff --git a/app/views/helpers/export/opml.phtml b/app/views/helpers/export/opml.phtml
index 4df36b122..5acdff374 100644
--- a/app/views/helpers/export/opml.phtml
+++ b/app/views/helpers/export/opml.phtml
@@ -4,7 +4,7 @@
  * @param array<FreshRSS_Feed> $feeds
  * @return array<array<string,string|null>>
  */
-function feedsToOutlines($feeds, bool $excludeMutedFeeds = false): array {
+function feedsToOutlines(array $feeds, bool $excludeMutedFeeds = false): array {
 	$outlines = [];
 	foreach ($feeds as $feed) {
 		if ($feed->mute() && $excludeMutedFeeds) {
@@ -98,4 +98,6 @@ if (!empty($this->feeds)) {
 }
 
 $libopml = new \marienfressinaud\LibOpml\LibOpml(true);
-echo $libopml->render($opml_array);
+$opml = $libopml->render($opml_array);
+/** @var string $opml */
+echo $opml;
diff --git a/app/views/helpers/javascript_vars.phtml b/app/views/helpers/javascript_vars.phtml
index e108f5a34..03ed96a9e 100644
--- a/app/views/helpers/javascript_vars.phtml
+++ b/app/views/helpers/javascript_vars.phtml
@@ -72,4 +72,4 @@ echo htmlspecialchars(json_encode(array(
 		'unread' => rawurlencode(_i('unread')),
 	),
 	'extensions' => $extData,
-), JSON_UNESCAPED_UNICODE), ENT_NOQUOTES, 'UTF-8');
+), JSON_UNESCAPED_UNICODE) ?: '', ENT_NOQUOTES, 'UTF-8');
diff --git a/app/views/index/logs.phtml b/app/views/index/logs.phtml
index 54b7e1c6b..42be022d6 100644
--- a/app/views/index/logs.phtml
+++ b/app/views/index/logs.phtml
@@ -14,7 +14,7 @@
 	?>
 
 	<?php if (!empty($items)) { ?>
-	<?php $this->logsPaginator->render('logs_pagination.phtml', 0); ?>
+	<?php $this->logsPaginator->render('logs_pagination.phtml'); ?>
 	<div id="loglist-wrapper" class="table-wrapper">
 		<table id="loglist">
 			<thead>
@@ -41,7 +41,7 @@
 		</tbody>
 		</table>
 	</div>
-	<?php $this->logsPaginator->render('logs_pagination.phtml', 0); ?>
+	<?php $this->logsPaginator->render('logs_pagination.phtml'); ?>
 
 
 
diff --git a/app/views/index/normal.phtml b/app/views/index/normal.phtml
index 02b336bf7..ede772a78 100644
--- a/app/views/index/normal.phtml
+++ b/app/views/index/normal.phtml
@@ -40,7 +40,7 @@ $today = @strtotime('today');
 		// We most likely already have the feed object in cache
 		$this->feed = FreshRSS_CategoryDAO::findFeed($this->categories, $this->entry->feedId());
 		if ($this->feed == null) {
-			$this->feed = $this->entry->feed();
+			$this->feed = $this->entry->feed() ?: null;
 			if ($this->feed == null) {
 				$this->feed = FreshRSS_Feed::example();
 			}
diff --git a/app/views/stats/idle.phtml b/app/views/stats/idle.phtml
index fcab1e8e3..d94256860 100644
--- a/app/views/stats/idle.phtml
+++ b/app/views/stats/idle.phtml
@@ -45,7 +45,7 @@
 					<li class="item feed<?= $error_class, $empty_class, $mute_class ?>" title="<?= $error_title, $empty_title ?>">
 						<a class="configure open-slider" href="<?= _url('stats', 'feed', 'id', $feedInPeriod['id'], 'sub', 'idle') ?>" title="<?= _t('gen.action.manage') ?>"><?= _i('configure') ?></a>
 						<?php if (FreshRSS_Context::$user_conf->show_favicons): ?><img class="favicon" src="<?= $feedInPeriod['favicon'] ?>" alt="✇" loading="lazy" /><?php endif; ?>
-						<span title="<?= timestamptodate($feedInPeriod['last_date'], false) ?>"><?= $feedInPeriod['name'] ?>
+						<span title="<?= timestamptodate((int)($feedInPeriod['last_date']), false) ?>"><?= $feedInPeriod['name'] ?>
 							(<?= _t('admin.stats.number_entries', $feedInPeriod['nb_articles']) ?>)</span>
 					</li>
 				<?php } ?>