diff --git a/src/Model/Tag.php b/src/Model/Tag.php
index 398079e3c6..dac0401b2b 100644
--- a/src/Model/Tag.php
+++ b/src/Model/Tag.php
@@ -667,12 +667,11 @@ class Tag
 	 */
 	private static function getBlockedSQL(): string
 	{
-		$blocked_txt = DI::config()->get('system', 'blocked_tags');
-		if (empty($blocked_txt)) {
+		$blocked = Strings::getTagArrayByString(DI::config()->get('system', 'blocked_tags'));
+		if (empty($blocked)) {
 			return '';
 		}
 
-		$blocked = explode(',', $blocked_txt);
 		array_walk($blocked, function (&$value) {
 			$value = "'" . DBA::escape(trim($value)) . "'";
 		});
diff --git a/src/Module/Admin/Site.php b/src/Module/Admin/Site.php
index 22309b8eb7..6daa8dddf8 100644
--- a/src/Module/Admin/Site.php
+++ b/src/Module/Admin/Site.php
@@ -271,7 +271,7 @@ class Site extends BaseAdmin
 		$transactionConfig->set('system', 'explicit_content'       , $explicit_content);
 		$transactionConfig->set('system', 'proxify_content'        , $proxify_content);
 		$transactionConfig->set('system', 'local_search'           , $local_search);
-		$transactionConfig->set('system', 'blocked_tags'           , $blocked_tags);
+		$transactionConfig->set('system', 'blocked_tags'           , Strings::cleanTags($blocked_tags));
 		$transactionConfig->set('system', 'cache_contact_avatar'   , $cache_contact_avatar);
 		$transactionConfig->set('system', 'check_new_version_url'  , $check_new_version_url);
 
@@ -332,8 +332,8 @@ class Site extends BaseAdmin
 		
 		$transactionConfig->set('system', 'relay_directly'                , $relay_directly);
 		$transactionConfig->set('system', 'relay_scope'                   , $relay_scope);
-		$transactionConfig->set('system', 'relay_server_tags'             , $relay_server_tags);
-		$transactionConfig->set('system', 'relay_deny_tags'               , $relay_deny_tags);
+		$transactionConfig->set('system', 'relay_server_tags'             , Strings::cleanTags($relay_server_tags));
+		$transactionConfig->set('system', 'relay_deny_tags'               , Strings::cleanTags($relay_deny_tags));
 		$transactionConfig->set('system', 'relay_max_tags'                , $relay_max_tags);
 		$transactionConfig->set('system', 'relay_user_tags'               , $relay_user_tags);
 		$transactionConfig->set('system', 'relay_deny_undetected_language', $relay_deny_undetected_language);
diff --git a/src/Module/Settings/Channels.php b/src/Module/Settings/Channels.php
index d846a91be7..34ba0d1d80 100644
--- a/src/Module/Settings/Channels.php
+++ b/src/Module/Settings/Channels.php
@@ -34,6 +34,7 @@ use Friendica\Module\BaseSettings;
 use Friendica\Module\Response;
 use Friendica\Network\HTTPException;
 use Friendica\Util\Profiler;
+use Friendica\Util\Strings;
 use Psr\Log\LoggerInterface;
 
 class Channels extends BaseSettings
@@ -80,8 +81,8 @@ class Channels extends BaseSettings
 				'access-key'       => substr(mb_strtolower($request['new_access_key']), 0, 1),
 				'uid'              => $uid,
 				'circle'           => (int)$request['new_circle'],
-				'include-tags'     => $this->cleanTags($request['new_include_tags']),
-				'exclude-tags'     => $this->cleanTags($request['new_exclude_tags']),
+				'include-tags'     => Strings::cleanTags($request['new_include_tags']),
+				'exclude-tags'     => Strings::cleanTags($request['new_exclude_tags']),
 				'full-text-search' => $request['new_text_search'],
 				'media-type'       => ($request['new_image'] ? 1 : 0) | ($request['new_video'] ? 2 : 0) | ($request['new_audio'] ? 4 : 0),
 				'languages'        => $request['new_languages'],
@@ -109,8 +110,8 @@ class Channels extends BaseSettings
 				'access-key'       => substr(mb_strtolower($request['access_key'][$id]), 0, 1),
 				'uid'              => $uid,
 				'circle'           => (int)$request['circle'][$id],
-				'include-tags'     => $this->cleanTags($request['include_tags'][$id]),
-				'exclude-tags'     => $this->cleanTags($request['exclude_tags'][$id]),
+				'include-tags'     => Strings::cleanTags($request['include_tags'][$id]),
+				'exclude-tags'     => Strings::cleanTags($request['exclude_tags'][$id]),
 				'full-text-search' => $request['text_search'][$id],
 				'media-type'       => ($request['image'][$id] ? 1 : 0) | ($request['video'][$id] ? 2 : 0) | ($request['audio'][$id] ? 4 : 0),
 				'languages'        => $request['languages'][$id],
@@ -222,18 +223,4 @@ class Channels extends BaseSettings
 			'$form_security_token' => self::getFormSecurityToken('settings_channels'),
 		]);
 	}
-
-	private function cleanTags(string $tag_list): string
-	{
-		$tags = [];
-
-		$tagitems = explode(',', mb_strtolower($tag_list));
-		foreach ($tagitems as $tag) {
-			$tag = trim($tag, '# ');
-			if (!empty($tag)) {
-				$tags[] = preg_replace('#\s#u', '', $tag);
-			}
-		}
-		return implode(',', $tags);
-	}
 }
diff --git a/src/Module/WellKnown/XSocialRelay.php b/src/Module/WellKnown/XSocialRelay.php
index 50cfb8aa82..39b67de846 100644
--- a/src/Module/WellKnown/XSocialRelay.php
+++ b/src/Module/WellKnown/XSocialRelay.php
@@ -22,10 +22,10 @@
 namespace Friendica\Module\WellKnown;
 
 use Friendica\BaseModule;
-use Friendica\Core\System;
 use Friendica\DI;
 use Friendica\Model\Search;
 use Friendica\Protocol\Relay;
+use Friendica\Util\Strings;
 
 /**
  * Node subscription preferences for social relay systems
@@ -43,13 +43,7 @@ class XSocialRelay extends BaseModule
 		$userTags = [];
 
 		if ($scope == Relay::SCOPE_TAGS) {
-			$server_tags = $config->get('system', 'relay_server_tags');
-			$tagitems = explode(',', $server_tags);
-
-			/// @todo Check if it was better to use "strtolower" on the tags
-			foreach ($tagitems as $tag) {
-				$systemTags[] = trim($tag, '# ');
-			}
+			$systemTags = Strings::getTagArrayByString($config->get('system', 'relay_server_tags'));
 
 			if ($config->get('system', 'relay_user_tags')) {
 				$userTags = Search::getUserTags();
diff --git a/src/Protocol/Relay.php b/src/Protocol/Relay.php
index db61e34791..3c655f8cb7 100644
--- a/src/Protocol/Relay.php
+++ b/src/Protocol/Relay.php
@@ -97,20 +97,13 @@ class Relay
 
 		$body = ActivityPub\Processor::normalizeMentionLinks($body);
 
-		$denyTags = [];
-
 		if ($scope == self::SCOPE_TAGS) {
 			$tagList = self::getSubscribedTags();
 		} else {
 			$tagList  = [];
 		}
 
-		$deny_tags = $config->get('system', 'relay_deny_tags');
-		$tagitems = explode(',', mb_strtolower($deny_tags));
-		foreach ($tagitems as $tag) {
-			$tag = trim($tag, '# ');
-			$denyTags[] = $tag;
-		}
+		$denyTags = Strings::getTagArrayByString($config->get('system', 'relay_deny_tags'));
 
 		if (!empty($tagList) || !empty($denyTags)) {
 			$content = mb_strtolower(BBCode::toPlaintext($body, false));
@@ -168,10 +161,7 @@ class Relay
 	 */
 	public static function getSubscribedTags(): array
 	{
-		$tags  = [];
-		foreach (explode(',', mb_strtolower(DI::config()->get('system', 'relay_server_tags'))) as $tag) {
-			$tags[] = trim($tag, '# ');
-		}
+		$tags = Strings::getTagArrayByString(DI::config()->get('system', 'relay_server_tags'));
 
 		if (DI::config()->get('system', 'relay_user_tags')) {
 			$tags = array_merge($tags, Search::getUserTags());
diff --git a/src/Util/Strings.php b/src/Util/Strings.php
index fff218e466..34029648ee 100644
--- a/src/Util/Strings.php
+++ b/src/Util/Strings.php
@@ -578,4 +578,36 @@ class Strings
 
 		return $styled_url;
 	}
+
+	/**
+	 * Sort a comma separated list of hashtags, convert them to lowercase and remove duplicates
+	 *
+	 * @param string $tag_list
+	 * @return string
+	 */
+	public static function cleanTags(string $tag_list): string
+	{
+		$tags = [];
+
+		$tagitems = explode(',', str_replace([' ', ';', '#'], ',', mb_strtolower($tag_list)));
+		foreach ($tagitems as $tag) {
+			if (!empty($tag)) {
+				$tags[] = preg_replace('#\s#u', '', $tag);
+			}
+		}
+		$tags = array_unique($tags);
+		asort($tags);
+		return implode(',', $tags);
+	}
+
+	/**
+	 * Get a tag array out of a comma separated list of tags
+	 *
+	 * @param string $tag_list
+	 * @return array
+	 */
+	public static function getTagArrayByString(string $tag_list): array
+	{
+		return explode(',', self::cleanTags($tag_list));
+	}
 }