diff --git a/src/BaseDepository.php b/src/BaseDepository.php
index 00d3bcfdfd..18cca9d30e 100644
--- a/src/BaseDepository.php
+++ b/src/BaseDepository.php
@@ -5,6 +5,7 @@ namespace Friendica;
 use Exception;
 use Friendica\Capabilities\ICanCreateFromTableRow;
 use Friendica\Database\Database;
+use Friendica\Database\DBA;
 use Friendica\Network\HTTPException\NotFoundException;
 use Psr\Log\LoggerInterface;
 
@@ -43,6 +44,67 @@ abstract class BaseDepository
 		$this->factory = $factory;
 	}
 
+	/**
+	 * Populates the collection according to the condition. Retrieves a limited subset of entities depending on the
+	 * boundaries and the limit. The total count of rows matching the condition is stored in the collection.
+	 *
+	 * Depends on the corresponding table featuring a numerical auto incremented column called `id`.
+	 *
+	 * max_id and min_id are susceptible to the query order:
+	 * - min_id alone only reliably works with ASC order
+	 * - max_id alone only reliably works with DESC order
+	 * If the wrong order is detected in either case, we reverse the query order and the entity list order after the query
+	 *
+	 * Chainable.
+	 *
+	 * @param array    $condition
+	 * @param array    $params
+	 * @param int|null $min_id Retrieve models with an id no fewer than this, as close to it as possible
+	 * @param int|null $max_id Retrieve models with an id no greater than this, as close to it as possible
+	 * @param int      $limit
+	 * @return BaseCollection
+	 * @throws \Exception
+	 */
+	protected function _selectByBoundaries(
+		array $condition = [],
+		array $params = [],
+		int $min_id = null,
+		int $max_id = null,
+		int $limit = self::LIMIT
+	): BaseCollection {
+		$totalCount = $this->count($condition);
+
+		$boundCondition = $condition;
+
+		$reverseOrder = false;
+
+		if (isset($min_id)) {
+			$boundCondition = DBA::mergeConditions($boundCondition, ['`id` > ?', $min_id]);
+			if (!isset($max_id) && isset($params['order']['id']) && ($params['order']['id'] === true || $params['order']['id'] === 'DESC')) {
+				$reverseOrder = true;
+
+				$params['order']['id'] = 'ASC';
+			}
+		}
+
+		if (isset($max_id)) {
+			$boundCondition = DBA::mergeConditions($boundCondition, ['`id` < ?', $max_id]);
+			if (!isset($min_id) && (!isset($params['order']['id']) || $params['order']['id'] === false || $params['order']['id'] === 'ASC')) {
+				$reverseOrder = true;
+
+				$params['order']['id'] = 'DESC';
+			}
+		}
+
+		$params['limit'] = $limit;
+
+		$Entities = $this->_select($boundCondition, $params);
+		if ($reverseOrder) {
+			$Entities->reverse();
+		}
+
+		return new BaseCollection($Entities->getArrayCopy(), $totalCount);
+	}
 
 	/**
 	 * @param array $condition
diff --git a/src/Navigation/Notifications/Collection/Notifications.php b/src/Navigation/Notifications/Collection/Notifications.php
new file mode 100644
index 0000000000..f383b4ccb0
--- /dev/null
+++ b/src/Navigation/Notifications/Collection/Notifications.php
@@ -0,0 +1,43 @@
+<?php
+/**
+ * @copyright Copyright (C) 2010-2021, the Friendica project
+ *
+ * @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 <https://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace Friendica\Navigation\Notifications\Collection;
+
+use Friendica\BaseCollection;
+use Friendica\Navigation\Notifications\Entity;
+
+class Notifications extends BaseCollection
+{
+	/**
+	 * @return Entity\Notification
+	 */
+	public function current(): Entity\Notification
+	{
+		return parent::current();
+	}
+
+	public function setSeen(): Notifications
+	{
+		return $this->map(function (Entity\Notification $Notification) {
+			$Notification->setSeen();
+		});
+	}
+}
diff --git a/src/Navigation/Notifications/Depository/Notification.php b/src/Navigation/Notifications/Depository/Notification.php
new file mode 100644
index 0000000000..a93bce6657
--- /dev/null
+++ b/src/Navigation/Notifications/Depository/Notification.php
@@ -0,0 +1,141 @@
+<?php
+
+namespace Friendica\Navigation\Notifications\Depository;
+
+use Exception;
+use Friendica\BaseCollection;
+use Friendica\BaseDepository;
+use Friendica\Database\Database;
+use Friendica\Database\DBA;
+use Friendica\Model\Verb;
+use Friendica\Navigation\Notifications\Collection;
+use Friendica\Navigation\Notifications\Entity;
+use Friendica\Navigation\Notifications\Factory;
+use Friendica\Network\HTTPException\NotFoundException;
+use Friendica\Util\DateTimeFormat;
+use Psr\Log\LoggerInterface;
+
+class Notification extends BaseDepository
+{
+	/** @var Factory\Notification  */
+	protected $factory;
+
+	protected static $table_name = 'notification';
+
+	public function __construct(Database $database, LoggerInterface $logger, Factory\Notification $factory = null)
+	{
+		parent::__construct($database, $logger, $factory ?? new Factory\Notification($logger));
+	}
+
+	/**
+	 * @param array $condition
+	 * @param array $params
+	 * @return Entity\Notification
+	 * @throws NotFoundException
+	 */
+	private function selectOne(array $condition, array $params = []): Entity\Notification
+	{
+		return parent::_selectOne($condition, $params);
+	}
+
+	private function select(array $condition, array $params = []): Collection\Notifications
+	{
+		return new Collection\Notifications(parent::_select($condition, $params)->getArrayCopy());
+	}
+
+	public function countForUser($uid, array $condition, array $params = []): int
+	{
+		$condition = DBA::mergeConditions($condition, ['uid' => $uid]);
+
+		return $this->count($condition, $params);
+	}
+
+	public function existsForUser($uid, array $condition): bool
+	{
+		$condition = DBA::mergeConditions($condition, ['uid' => $uid]);
+
+		return $this->exists($condition);
+	}
+
+	/**
+	 * @param int $id
+	 * @return Entity\Notification
+	 * @throws NotFoundException
+	 */
+	public function selectOneById(int $id): Entity\Notification
+	{
+		return $this->selectOne(['id' => $id]);
+	}
+
+	public function selectOneForUser(int $uid, array $condition, array $params = []): Entity\Notification
+	{
+		$condition = DBA::mergeConditions($condition, ['uid' => $uid]);
+
+		return $this->selectOne($condition, $params);
+	}
+
+	public function selectForUser(int $uid, array $condition = [], array $params = []): Collection\Notifications
+	{
+		$condition = DBA::mergeConditions($condition, ['uid' => $uid]);
+
+		return $this->select($condition, $params);
+	}
+
+	public function selectAllForUser(int $uid): Collection\Notifications
+	{
+		return $this->selectForUser($uid);
+	}
+
+	/**
+	 * @param array    $condition
+	 * @param array    $params
+	 * @param int|null $min_id Retrieve models with an id no fewer than this, as close to it as possible
+	 * @param int|null $max_id Retrieve models with an id no greater than this, as close to it as possible
+	 * @param int      $limit
+	 * @return BaseCollection
+	 * @throws Exception
+	 * @see _selectByBoundaries
+	 */
+	public function selectByBoundaries(array $condition = [], array $params = [], int $min_id = null, int $max_id = null, int $limit = self::LIMIT)
+	{
+		$BaseCollection = parent::_selectByBoundaries($condition, $params, $min_id, $max_id, $limit);
+
+		return new Collection\Notifications($BaseCollection->getArrayCopy(), $BaseCollection->getTotalCount());
+	}
+
+	public function setAllSeenForUser(int $uid, array $condition = []): bool
+	{
+		$condition = DBA::mergeConditions($condition, ['uid' => $uid]);
+
+		return $this->db->update(self::$table_name, ['seen' => true], $condition);
+	}
+
+	/**
+	 * @param Entity\Notification $Notification
+	 * @return Entity\Notification
+	 * @throws Exception
+	 */
+	public function save(Entity\Notification $Notification): Entity\Notification
+	{
+		$fields = [
+			'uid'           => $Notification->uid,
+			'vid'           => Verb::getID($Notification->verb),
+			'type'          => $Notification->type,
+			'actor-id'      => $Notification->actorId,
+			'target-uri-id' => $Notification->targetUriId,
+			'parent-uri-id' => $Notification->parentUriId,
+			'seen'          => $Notification->seen,
+		];
+
+		if ($Notification->id) {
+			$this->db->update(self::$table_name, $fields, ['id' => $Notification->id]);
+		} else {
+			$fields['created'] = DateTimeFormat::utcNow();
+			$this->db->insert(self::$table_name, $fields);
+
+			$Notification = $this->selectOneById($this->db->lastInsertId());
+		}
+
+		return $Notification;
+	}
+}
diff --git a/src/Navigation/Notifications/Entity/Notification.php b/src/Navigation/Notifications/Entity/Notification.php
new file mode 100644
index 0000000000..3f491f98c0
--- /dev/null
+++ b/src/Navigation/Notifications/Entity/Notification.php
@@ -0,0 +1,74 @@
+<?php
+
+namespace Friendica\Navigation\Notifications\Entity;
+
+use DateTime;
+use Friendica\BaseEntity;
+
+/**
+ * @property-read $id
+ * @property-read $uid
+ * @property-read $verb
+ * @property-read $type
+ * @property-read $actorId
+ * @property-read $targetUriId
+ * @property-read $parentUriId
+ * @property-read $created
+ * @property-read $seen
+ */
+class Notification extends BaseEntity
+{
+	/** @var int */
+	protected $id;
+	/** @var int */
+	protected $uid;
+	/** @var string */
+	protected $verb;
+	/**
+	 * @var int One of the \Friendica\Model\Post\UserNotification::TYPE_* constant values
+	 * @see \Friendica\Model\Post\UserNotification
+	 */
+	protected $type;
+	/** @var int */
+	protected $actorId;
+	/** @var int */
+	protected $targetUriId;
+	/** @var int */
+	protected $parentUriId;
+	/** @var DateTime */
+	protected $created;
+	/** @var bool */
+	protected $seen;
+
+	/**
+	 * Please do not use this constructor directly, instead use one of the method of the Notification factory.
+	 *
+	 * @param int           $uid
+	 * @param string        $verb
+	 * @param int           $type
+	 * @param int           $actorId
+	 * @param int|null      $targetUriId
+	 * @param int|null      $parentUriId
+	 * @param DateTime|null $created
+	 * @param bool          $seen
+	 * @param int|null      $id
+	 * @see \Friendica\Navigation\Notifications\Factory\Notification
+	 */
+	public function __construct(int $uid, string $verb, int $type, int $actorId, int $targetUriId = null, int $parentUriId = null, DateTime $created = null, bool $seen = false, int $id = null)
+	{
+		$this->uid         = $uid;
+		$this->verb        = $verb;
+		$this->type        = $type;
+		$this->actorId     = $actorId;
+		$this->targetUriId = $targetUriId;
+		$this->parentUriId = $parentUriId ?: $targetUriId;
+		$this->created     = $created;
+		$this->seen        = $seen;
+		$this->id          = $id;
+	}
+
+	public function setSeen()
+	{
+		$this->seen = true;
+	}
+}
diff --git a/src/Navigation/Notifications/Exception/UnexpectedNotificationTypeException.php b/src/Navigation/Notifications/Exception/UnexpectedNotificationTypeException.php
new file mode 100644
index 0000000000..e370608af5
--- /dev/null
+++ b/src/Navigation/Notifications/Exception/UnexpectedNotificationTypeException.php
@@ -0,0 +1,7 @@
+<?php
+
+namespace Friendica\Navigation\Notifications\Exception;
+
+class UnexpectedNotificationTypeException extends \Exception
+{
+}
diff --git a/src/Navigation/Notifications/Factory/Introduction.php b/src/Navigation/Notifications/Factory/Introduction.php
new file mode 100644
index 0000000000..0baf0385c6
--- /dev/null
+++ b/src/Navigation/Notifications/Factory/Introduction.php
@@ -0,0 +1,187 @@
+<?php
+/**
+ * @copyright Copyright (C) 2010-2021, the Friendica project
+ *
+ * @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 <https://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace Friendica\Navigation\Notifications\Factory;
+
+use Exception;
+use Friendica\App;
+use Friendica\App\BaseURL;
+use Friendica\BaseFactory;
+use Friendica\Content\Text\BBCode;
+use Friendica\Core\L10n;
+use Friendica\Core\PConfig\IPConfig;
+use Friendica\Core\Protocol;
+use Friendica\Core\Session\ISession;
+use Friendica\Database\Database;
+use Friendica\Model\Contact;
+use Friendica\Module\BaseNotifications;
+use Friendica\Navigation\Notifications\ValueObject;
+use Friendica\Util\Proxy;
+use Psr\Log\LoggerInterface;
+
+/**
+ * Factory for creating notification objects based on introductions
+ * Currently, there are two main types of introduction based notifications:
+ * - Friend suggestion
+ * - Friend/Follower request
+ */
+class Introduction extends BaseFactory
+{
+	/** @var Database */
+	private $dba;
+	/** @var BaseURL */
+	private $baseUrl;
+	/** @var L10n */
+	private $l10n;
+	/** @var IPConfig */
+	private $pConfig;
+	/** @var ISession */
+	private $session;
+	/** @var string */
+	private $nick;
+
+	public function __construct(LoggerInterface $logger, Database $dba, BaseURL $baseUrl, L10n $l10n, App $app, IPConfig $pConfig, ISession $session)
+	{
+		parent::__construct($logger);
+
+		$this->dba          = $dba;
+		$this->baseUrl      = $baseUrl;
+		$this->l10n         = $l10n;
+		$this->pConfig      = $pConfig;
+		$this->session      = $session;
+		$this->nick         = $app->getLoggedInUserNickname() ?? '';
+	}
+
+	/**
+	 * Get introductions
+	 *
+	 * @param bool $all     If false only include introductions into the query
+	 *                      which aren't marked as ignored
+	 * @param int  $start   Start the query at this point
+	 * @param int  $limit   Maximum number of query results
+	 * @param int  $id      When set, only the introduction with this id is displayed
+	 *
+	 * @return ValueObject\Introduction[]
+	 */
+	public function getList(bool $all = false, int $start = 0, int $limit = BaseNotifications::DEFAULT_PAGE_LIMIT, int $id = 0): array
+	{
+		$sql_extra = "";
+
+		if (empty($id)) {
+			if (!$all) {
+				$sql_extra = " AND NOT `ignore` ";
+			}
+
+			$sql_extra .= " AND NOT `intro`.`blocked` ";
+		} else {
+			$sql_extra = sprintf(" AND `intro`.`id` = %d ", $id);
+		}
+
+		$formattedIntroductions = [];
+
+		try {
+			/// @todo Fetch contact details by "Contact::getByUrl" instead of queries to contact and fcontact
+			$stmtNotifications = $this->dba->p(
+				"SELECT `intro`.`id` AS `intro_id`, `intro`.*, `contact`.*,
+				`fcontact`.`name` AS `fname`, `fcontact`.`url` AS `furl`, `fcontact`.`addr` AS `faddr`,
+				`fcontact`.`photo` AS `fphoto`, `fcontact`.`request` AS `frequest`
+			FROM `intro`
+				LEFT JOIN `contact` ON `contact`.`id` = `intro`.`contact-id`
+				LEFT JOIN `fcontact` ON `intro`.`fid` = `fcontact`.`id`
+			WHERE `intro`.`uid` = ? $sql_extra
+			LIMIT ?, ?",
+				$_SESSION['uid'],
+				$start,
+				$limit
+			);
+
+			while ($intro = $this->dba->fetch($stmtNotifications)) {
+				if (empty($intro['url'])) {
+					continue;
+				}
+
+			// There are two kind of introduction. Contacts suggested by other contacts and normal connection requests.
+				// We have to distinguish between these two because they use different data.
+				// Contact suggestions
+				if ($intro['fid'] ?? '') {
+					if (empty($intro['furl'])) {
+						continue;
+					}
+					$return_addr = bin2hex($this->nick . '@' .
+					                       $this->baseUrl->getHostname() .
+					                       (($this->baseUrl->getUrlPath()) ? '/' . $this->baseUrl->getUrlPath() : ''));
+
+					$formattedIntroductions[] = new ValueObject\Introduction([
+						'label'          => 'friend_suggestion',
+						'str_type'       => $this->l10n->t('Friend Suggestion'),
+						'intro_id'       => $intro['intro_id'],
+						'madeby'         => $intro['name'],
+						'madeby_url'     => $intro['url'],
+						'madeby_zrl'     => Contact::magicLink($intro['url']),
+						'madeby_addr'    => $intro['addr'],
+						'contact_id'     => $intro['contact-id'],
+						'photo'          => Contact::getAvatarUrlForUrl($intro['furl'], 0, Proxy::SIZE_SMALL),
+						'name'           => $intro['fname'],
+						'url'            => $intro['furl'],
+						'zrl'            => Contact::magicLink($intro['furl']),
+						'hidden'         => $intro['hidden'] == 1,
+						'post_newfriend' => (intval($this->pConfig->get(local_user(), 'system', 'post_newfriend')) ? '1' : 0),
+						'note'           => $intro['note'],
+						'request'        => $intro['frequest'] . '?addr=' . $return_addr]);
+
+					// Normal connection requests
+				} else {
+					// Don't show these data until you are connected. Diaspora is doing the same.
+					if ($intro['network'] === Protocol::DIASPORA) {
+						$intro['location'] = "";
+						$intro['about']    = "";
+					}
+
+					$formattedIntroductions[] = new ValueObject\Introduction([
+						'label'          => (($intro['network'] !== Protocol::OSTATUS) ? 'friend_request' : 'follower'),
+						'str_type'       => (($intro['network'] !== Protocol::OSTATUS) ? $this->l10n->t('Friend/Connect Request') : $this->l10n->t('New Follower')),
+						'dfrn_id'        => $intro['issued-id'],
+						'uid'            => $this->session->get('uid'),
+						'intro_id'       => $intro['intro_id'],
+						'contact_id'     => $intro['contact-id'],
+						'photo'          => Contact::getPhoto($intro),
+						'name'           => $intro['name'],
+						'location'       => BBCode::convert($intro['location'], false),
+						'about'          => BBCode::convert($intro['about'], false),
+						'keywords'       => $intro['keywords'],
+						'hidden'         => $intro['hidden'] == 1,
+						'post_newfriend' => (intval($this->pConfig->get(local_user(), 'system', 'post_newfriend')) ? '1' : 0),
+						'url'            => $intro['url'],
+						'zrl'            => Contact::magicLink($intro['url']),
+						'addr'           => $intro['addr'],
+						'network'        => $intro['network'],
+						'knowyou'        => $intro['knowyou'],
+						'note'           => $intro['note'],
+					]);
+				}
+			}
+		} catch (Exception $e) {
+			$this->logger->warning('Select failed.', ['uid' => $_SESSION['uid'], 'exception' => $e]);
+		}
+
+		return $formattedIntroductions;
+	}
+}
diff --git a/src/Navigation/Notifications/Factory/Notification.php b/src/Navigation/Notifications/Factory/Notification.php
new file mode 100644
index 0000000000..e8ff9ea30f
--- /dev/null
+++ b/src/Navigation/Notifications/Factory/Notification.php
@@ -0,0 +1,235 @@
+<?php
+
+namespace Friendica\Navigation\Notifications\Factory;
+
+use Friendica\App\BaseURL;
+use Friendica\BaseFactory;
+use Friendica\Capabilities\ICanCreateFromTableRow;
+use Friendica\Content\Text\Plaintext;
+use Friendica\Core\L10n;
+use Friendica\Model\Contact;
+use Friendica\Model\Post;
+use Friendica\Model\Verb;
+use Friendica\Navigation\Notifications\Entity;
+use Friendica\Protocol\Activity;
+
+class Notification extends BaseFactory implements ICanCreateFromTableRow
+{
+	public function createFromTableRow(array $row): Entity\Notification
+	{
+		return new Entity\Notification(
+			$row['uid'] ?? 0,
+			Verb::getByID($row['vid']),
+			$row['type'],
+			$row['actor-id'],
+			$row['target-uri-id'],
+			$row['parent-uri-id'],
+			new \DateTime($row['created'], new \DateTimeZone('UTC')),
+			$row['seen'],
+			$row['id']
+		);
+	}
+
+	public function createForUser(int $uid, int $vid, int $type, int $actorId, int $targetUriId, int $parentUriId): Entity\Notification
+	{
+		return new Entity\Notification(
+			$uid,
+			Verb::getByID($vid),
+			$type,
+			$actorId,
+			$targetUriId,
+			$parentUriId
+		);
+	}
+
+	public function createForRelationship(int $uid, int $contactId, string $verb): Entity\Notification
+	{
+		return new Entity\Notification(
+			$uid,
+			$verb,
+			Post\UserNotification::TYPE_NONE,
+			$contactId
+		);
+	}
+
+	/**
+	 * @param Entity\Notification $Notification
+	 * @param BaseURL             $baseUrl
+	 * @param L10n                $userL10n Seeded with the language of the user we mean the notification for
+	 * @return array
+	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
+	 */
+	public function getMessageFromNotification(Entity\Notification $Notification, BaseURL $baseUrl, L10n $userL10n)
+	{
+		$message = [];
+
+		$causer = $author = Contact::getById($Notification->actorId, ['id', 'name', 'url', 'pending']);
+		if (empty($causer)) {
+			$this->logger->info('Causer not found', ['contact' => $Notification->actorId]);
+			return $message;
+		}
+
+		if ($Notification->type === Post\UserNotification::TYPE_NONE) {
+			if ($causer['pending']) {
+				$msg = $userL10n->t('%1$s wants to follow you');
+			} else {
+				$msg = $userL10n->t('%1$s had started following you');
+			}
+			$title = $causer['name'];
+			$link  = $baseUrl . '/contact/' . $causer['id'];
+		} else {
+			if (!$Notification->targetUriId) {
+				return $message;
+			}
+
+			if (in_array($Notification->type, [Post\UserNotification::TYPE_THREAD_COMMENT, Post\UserNotification::TYPE_COMMENT_PARTICIPATION, Post\UserNotification::TYPE_ACTIVITY_PARTICIPATION, Post\UserNotification::TYPE_EXPLICIT_TAGGED])) {
+				$item = Post::selectFirst([], ['uri-id' => $Notification->parentUriId, 'uid' => [0, $Notification->uid]], ['order' => ['uid' => true]]);
+				if (empty($item)) {
+					$this->logger->info('Parent post not found', ['uri-id' => $Notification->parentUriId]);
+					return $message;
+				}
+			} else {
+				$item = Post::selectFirst([], ['uri-id' => $Notification->targetUriId, 'uid' => [0, $Notification->uid]], ['order' => ['uid' => true]]);
+				if (empty($item)) {
+					$this->logger->info('Post not found', ['uri-id' => $Notification->targetUriId]);
+					return $message;
+				}
+
+				if ($Notification->verb == Activity::POST) {
+					$item = Post::selectFirst([], ['uri-id' => $item['thr-parent-id'], 'uid' => [0, $Notification->uid]], ['order' => ['uid' => true]]);
+					if (empty($item)) {
+						$this->logger->info('Thread parent post not found', ['uri-id' => $item['thr-parent-id']]);
+						return $message;
+					}
+				}
+			}
+
+			if ($item['owner-id'] != $item['author-id']) {
+				$cid = $item['owner-id'];
+			}
+			if (!empty($item['causer-id']) && ($item['causer-id'] != $item['author-id'])) {
+				$cid = $item['causer-id'];
+			}
+
+			if (($Notification->type === Post\UserNotification::TYPE_SHARED) && !empty($cid)) {
+				$causer = Contact::getById($cid, ['id', 'name', 'url']);
+				if (empty($causer)) {
+					$this->logger->info('Causer not found', ['causer' => $cid]);
+					return $message;
+				}
+			} elseif (in_array($Notification->type, [Post\UserNotification::TYPE_COMMENT_PARTICIPATION, Post\UserNotification::TYPE_ACTIVITY_PARTICIPATION])) {
+				$author = Contact::getById($item['author-id'], ['id', 'name', 'url']);
+				if (empty($author)) {
+					$this->logger->info('Author not found', ['author' => $item['author-id']]);
+					return $message;
+				}
+			}
+
+			$link = $baseUrl . '/display/' . urlencode($item['guid']);
+
+			$content = Plaintext::getPost($item, 70);
+			if (!empty($content['text'])) {
+				$title = '"' . trim(str_replace("\n", " ", $content['text'])) . '"';
+			} else {
+				$title = '';
+			}
+
+			switch ($Notification->verb) {
+				case Activity::LIKE:
+					switch ($Notification->type) {
+						case Post\UserNotification::TYPE_DIRECT_COMMENT:
+							$msg = $userL10n->t('%1$s liked your comment %2$s');
+							break;
+						case Post\UserNotification::TYPE_DIRECT_THREAD_COMMENT:
+							$msg = $userL10n->t('%1$s liked your post %2$s');
+							break;
+					}
+					break;
+				case Activity::DISLIKE:
+					switch ($Notification->type) {
+						case Post\UserNotification::TYPE_DIRECT_COMMENT:
+							$msg = $userL10n->t('%1$s disliked your comment %2$s');
+							break;
+						case Post\UserNotification::TYPE_DIRECT_THREAD_COMMENT:
+							$msg = $userL10n->t('%1$s disliked your post %2$s');
+							break;
+					}
+					break;
+				case Activity::ANNOUNCE:
+					switch ($Notification->type) {
+						case Post\UserNotification::TYPE_DIRECT_COMMENT:
+							$msg = $userL10n->t('%1$s shared your comment %2$s');
+							break;
+						case Post\UserNotification::TYPE_DIRECT_THREAD_COMMENT:
+							$msg = $userL10n->t('%1$s shared your post %2$s');
+							break;
+					}
+					break;
+				case Activity::POST:
+					switch ($Notification->type) {
+						case Post\UserNotification::TYPE_EXPLICIT_TAGGED:
+							$msg = $userL10n->t('%1$s tagged you on %2$s');
+							break;
+
+						case Post\UserNotification::TYPE_IMPLICIT_TAGGED:
+							$msg = $userL10n->t('%1$s replied to you on %2$s');
+							break;
+
+						case Post\UserNotification::TYPE_THREAD_COMMENT:
+							$msg = $userL10n->t('%1$s commented in your thread %2$s');
+							break;
+
+						case Post\UserNotification::TYPE_DIRECT_COMMENT:
+							$msg = $userL10n->t('%1$s commented on your comment %2$s');
+							break;
+
+						case Post\UserNotification::TYPE_COMMENT_PARTICIPATION:
+						case Post\UserNotification::TYPE_ACTIVITY_PARTICIPATION:
+							if (($causer['id'] == $author['id']) && ($title != '')) {
+								$msg = $userL10n->t('%1$s commented in their thread %2$s');
+							} elseif ($causer['id'] == $author['id']) {
+								$msg = $userL10n->t('%1$s commented in their thread');
+							} elseif ($title != '') {
+								$msg = $userL10n->t('%1$s commented in the thread %2$s from %3$s');
+							} else {
+								$msg = $userL10n->t('%1$s commented in the thread from %3$s');
+							}
+							break;
+
+						case Post\UserNotification::TYPE_DIRECT_THREAD_COMMENT:
+							$msg = $userL10n->t('%1$s commented on your thread %2$s');
+							break;
+
+						case Post\UserNotification::TYPE_SHARED:
+							if (($causer['id'] != $author['id']) && ($title != '')) {
+								$msg = $userL10n->t('%1$s shared the post %2$s from %3$s');
+							} elseif ($causer['id'] != $author['id']) {
+								$msg = $userL10n->t('%1$s shared a post from %3$s');
+							} elseif ($title != '') {
+								$msg = $userL10n->t('%1$s shared the post %2$s');
+							} else {
+								$msg = $userL10n->t('%1$s shared a post');
+							}
+							break;
+					}
+					break;
+			}
+		}
+
+		if (!empty($msg)) {
+			// Name of the notification's causer
+			$message['causer'] = $causer['name'];
+			// Format for the "ping" mechanism
+			$message['notification'] = sprintf($msg, '{0}', $title, $author['name']);
+			// Plain text for the web push api
+			$message['plain'] = sprintf($msg, $causer['name'], $title, $author['name']);
+			// Rich text for other purposes
+			$message['rich'] = sprintf($msg,
+				'[url=' . $causer['url'] . ']' . $causer['name'] . '[/url]',
+				'[url=' . $link . ']' . $title . '[/url]',
+				'[url=' . $author['url'] . ']' . $author['name'] . '[/url]');
+		}
+
+		return $message;
+	}
+}
diff --git a/src/Navigation/Notifications/ValueObject/Introduction.php b/src/Navigation/Notifications/ValueObject/Introduction.php
new file mode 100644
index 0000000000..332f6ccf60
--- /dev/null
+++ b/src/Navigation/Notifications/ValueObject/Introduction.php
@@ -0,0 +1,241 @@
+<?php
+/**
+ * @copyright Copyright (C) 2010-2021, the Friendica project
+ *
+ * @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 <https://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace Friendica\Navigation\Notifications\ValueObject;
+
+/**
+ * A view-only object for printing introduction notifications to the frontend
+ */
+class Introduction implements \JsonSerializable
+{
+	/** @var string */
+	private $label;
+	/** @var string */
+	private $type;
+	/** @var int */
+	private $intro_id;
+	/** @var string */
+	private $madeBy;
+	/** @var string */
+	private $madeByUrl;
+	/** @var string */
+	private $madeByZrl;
+	/** @var string */
+	private $madeByAddr;
+	/** @var int */
+	private $contactId;
+	/** @var string */
+	private $photo;
+	/** @var string */
+	private $name;
+	/** @var string */
+	private $url;
+	/** @var string */
+	private $zrl;
+	/** @var boolean */
+	private $hidden;
+	/** @var int */
+	private $postNewFriend;
+	/** @var boolean */
+	private $knowYou;
+	/** @var string */
+	private $note;
+	/** @var string */
+	private $request;
+	/** @var int */
+	private $dfrnId;
+	/** @var string */
+	private $addr;
+	/** @var string */
+	private $network;
+	/** @var int */
+	private $uid;
+	/** @var string */
+	private $keywords;
+	/** @var string */
+	private $location;
+	/** @var string */
+	private $about;
+
+	public function getLabel(): string
+	{
+		return $this->label;
+	}
+
+	public function getType(): string
+	{
+		return $this->type;
+	}
+
+	public function getIntroId(): int
+	{
+		return $this->intro_id;
+	}
+
+	public function getMadeBy(): string
+	{
+		return $this->madeBy;
+	}
+
+	public function getMadeByUrl(): string
+	{
+		return $this->madeByUrl;
+	}
+
+	public function getMadeByZrl(): string
+	{
+		return $this->madeByZrl;
+	}
+
+	public function getMadeByAddr(): string
+	{
+		return $this->madeByAddr;
+	}
+
+	public function getContactId(): int
+	{
+		return $this->contactId;
+	}
+
+	public function getPhoto(): string
+	{
+		return $this->photo;
+	}
+
+	public function getName(): string
+	{
+		return $this->name;
+	}
+
+	public function getUrl(): string
+	{
+		return $this->url;
+	}
+
+	public function getZrl(): string
+	{
+		return $this->zrl;
+	}
+
+	public function isHidden(): bool
+	{
+		return $this->hidden;
+	}
+
+	public function getPostNewFriend(): int
+	{
+		return $this->postNewFriend;
+	}
+
+	public function getKnowYou(): string
+	{
+		return $this->knowYou;
+	}
+
+	public function getNote(): string
+	{
+		return $this->note;
+	}
+
+	public function getRequest(): string
+	{
+		return $this->request;
+	}
+
+	public function getDfrnId(): int
+	{
+		return $this->dfrnId;
+	}
+
+	public function getAddr(): string
+	{
+		return $this->addr;
+	}
+
+	public function getNetwork(): string
+	{
+		return $this->network;
+	}
+
+	public function getUid(): int
+	{
+		return $this->uid;
+	}
+
+	public function getKeywords(): string
+	{
+		return $this->keywords;
+	}
+
+	public function getLocation(): string
+	{
+		return $this->location;
+	}
+
+	public function getAbout(): string
+	{
+		return $this->about;
+	}
+
+	public function __construct(array $data = [])
+	{
+		$this->label         = $data['label'] ?? '';
+		$this->type          = $data['str_type'] ?? '';
+		$this->intro_id      = $data['intro_id'] ?? -1;
+		$this->madeBy        = $data['madeBy'] ?? '';
+		$this->madeByUrl     = $data['madeByUrl'] ?? '';
+		$this->madeByZrl     = $data['madeByZrl'] ?? '';
+		$this->madeByAddr    = $data['madeByAddr'] ?? '';
+		$this->contactId     = $data['contactId'] ?? -1;
+		$this->photo         = $data['photo'] ?? '';
+		$this->name          = $data['name'] ?? '';
+		$this->url           = $data['url'] ?? '';
+		$this->zrl           = $data['zrl'] ?? '';
+		$this->hidden        = $data['hidden'] ?? false;
+		$this->postNewFriend = $data['postNewFriend'] ?? '';
+		$this->knowYou       = $data['knowYou'] ?? false;
+		$this->note          = $data['note'] ?? '';
+		$this->request       = $data['request'] ?? '';
+		$this->dfrnId        = -1;
+		$this->addr          = $data['addr'] ?? '';
+		$this->network       = $data['network'] ?? '';
+		$this->uid           = $data['uid'] ?? -1;
+		$this->keywords      = $data['keywords'] ?? '';
+		$this->location      = $data['location'] ?? '';
+		$this->about         = $data['about'] ?? '';
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	public function jsonSerialize()
+	{
+		return $this->toArray();
+	}
+
+	/**
+	 * @return array
+	 */
+	public function toArray(): array
+	{
+		return get_object_vars($this);
+	}
+}