diff --git a/appinfo/info.xml b/appinfo/info.xml
index fa92974df..509bd746a 100755
--- a/appinfo/info.xml
+++ b/appinfo/info.xml
@@ -11,7 +11,7 @@
 		More information is available in the Activity documentation.
 	</description>
 
-	<version>2.21.0</version>
+	<version>2.21.1</version>
 	<licence>agpl</licence>
 	<author>Frank Karlitschek</author>
 	<author>Joas Schilling</author>
@@ -41,6 +41,7 @@
 		<job>OCA\Activity\BackgroundJob\EmailNotification</job>
 		<job>OCA\Activity\BackgroundJob\ExpireActivities</job>
 		<job>OCA\Activity\BackgroundJob\DigestMail</job>
+		<job>OCA\Activity\BackgroundJob\RemoveFormerActivitySettings</job>
 	</background-jobs>
 
 	<commands>
diff --git a/lib/BackgroundJob/RemoveFormerActivitySettings.php b/lib/BackgroundJob/RemoveFormerActivitySettings.php
new file mode 100644
index 000000000..096f8b7f2
--- /dev/null
+++ b/lib/BackgroundJob/RemoveFormerActivitySettings.php
@@ -0,0 +1,72 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * @copyright Copyright (c) 2023 Joas Schilling <coding@schilljs.com>
+ *
+ * @author Joas Schilling <coding@schilljs.com>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OCA\Activity\BackgroundJob;
+
+use OCP\Activity\IExtension;
+use OCP\Activity\IManager;
+use OCP\AppFramework\Utility\ITimeFactory;
+use OCP\BackgroundJob\TimedJob;
+use OCP\DB\QueryBuilder\IQueryBuilder;
+use OCP\IDBConnection;
+
+class RemoveFormerActivitySettings extends TimedJob {
+	public function __construct(
+		ITimeFactory $time,
+		protected IManager $manager,
+		protected IDBConnection $db,
+	) {
+		parent::__construct($time);
+		$this->setInterval(24 * 60 * 60);
+	}
+
+	protected function run($argument): void {
+		$preferencesToKeep = [
+			'notify_setting_activity_digest',
+			'notify_setting_batchtime',
+			'notify_setting_self',
+			'notify_setting_selfemail',
+		];
+		foreach ($this->manager->getSettings() as $setting) {
+			if ($setting->canChangeMail()) {
+				$preferencesToKeep[] = 'notify_' . IExtension::METHOD_MAIL . '_' . $setting->getIdentifier();
+			}
+			if ($setting->canChangeNotification()) {
+				$preferencesToKeep[] = 'notify_' . IExtension::METHOD_NOTIFICATION . '_' . $setting->getIdentifier();
+			}
+		}
+
+		$this->removeFormerPreference($preferencesToKeep);
+	}
+
+	protected function removeFormerPreference(array $preferencesToKeep): void {
+		$query = $this->db->getQueryBuilder();
+		$query->delete('preferences')
+			->where($query->expr()->eq('appid', $query->createNamedParameter('activity')))
+			->andWhere($query->expr()->like('configkey', $query->createNamedParameter($this->db->escapeLikeParameter('notify_') . '%')))
+			->andWhere($query->expr()->notIn('configkey', $query->createNamedParameter($preferencesToKeep, IQueryBuilder::PARAM_STR_ARRAY)));
+		$query->executeStatement();
+	}
+}