diff --git a/lib/private/Comments/Comment.php b/lib/private/Comments/Comment.php
index 7190f252c8232..90d4bbddd72e7 100644
--- a/lib/private/Comments/Comment.php
+++ b/lib/private/Comments/Comment.php
@@ -182,15 +182,7 @@ public function setMessage($message, $maxLength = self::MAX_MESSAGE_LENGTH): ICo
 	}
 
 	/**
-	 * returns an array containing mentions that are included in the comment
-	 *
-	 * @return array each mention provides a 'type' and an 'id', see example below
-	 * @psalm-return list<array{type: 'guest'|'email'|'federated_group'|'group'|'federated_team'|'team'|'federated_user'|'user', id: non-empty-lowercase-string}>
-	 * @since 30.0.2 Type 'email' is supported
-	 * @since 29.0.0 Types 'federated_group', 'federated_team', 'team' and 'federated_user' are supported
-	 * @since 23.0.0 Type 'group' is supported
-	 * @since 17.0.0 Type 'guest' is supported
-	 * @since 11.0.0
+	 * @inheritDoc
 	 */
 	public function getMentions(): array {
 		$ok = preg_match_all("/\B(?<![^a-z0-9_\-@\.\'\s])@(\"(guest|email)\/[a-f0-9]+\"|\"(?:federated_)?(?:group|team|user){1}\/[a-z0-9_\-@\.\' \/:]+\"|\"[a-z0-9_\-@\.\' ]+\"|[a-z0-9_\-@\.\']+)/i", $this->getMessage(), $mentions);
@@ -198,9 +190,6 @@ public function getMentions(): array {
 			return [];
 		}
 		$mentionIds = array_unique($mentions[0]);
-		usort($mentionIds, static function ($mentionId1, $mentionId2) {
-			return mb_strlen($mentionId2) <=> mb_strlen($mentionId1);
-		});
 		$result = [];
 		foreach ($mentionIds as $mentionId) {
 			// Cut-off the @ and remove wrapping double-quotes
@@ -237,6 +226,10 @@ public function getMentions(): array {
 				$result[] = ['type' => 'user', 'id' => $cleanId];
 			}
 		}
+		// Return sorted by id (descending length)
+		usort($result, static function ($mention1, $mention2) {
+			return mb_strlen($mention2['id']) <=> mb_strlen($mention1['id']);
+		});
 		return $result;
 	}
 
diff --git a/lib/public/Comments/IComment.php b/lib/public/Comments/IComment.php
index cdfcf188761be..dfe3bacb1a687 100644
--- a/lib/public/Comments/IComment.php
+++ b/lib/public/Comments/IComment.php
@@ -121,13 +121,19 @@ public function getMessage();
 	public function setMessage($message, $maxLength = self::MAX_MESSAGE_LENGTH);
 
 	/**
-	 * returns an array containing mentions that are included in the comment
+	 * Returns all mentions from the comment message.
 	 *
-	 * @return array each mention provides a 'type' and an 'id', see example below
+	 * Parses the message, returning an array of mentions.
+	 * Mentions are sorted by descending length of their id before being returned.
+	 *
+	 * Supported mention types: 'user', 'group', 'team', 'guest', 'email', 'federated_group', 'federated_team', 'federated_user'.
+	 *
+	 * @return array Each mention is an associative array with 'type' and 'id' keys, sorted by descending length.
 	 * @psalm-return list<array{type: 'guest'|'email'|'federated_group'|'group'|'federated_team'|'team'|'federated_user'|'user', id: non-empty-lowercase-string}>
 	 * @since 30.0.2 Type 'email' is supported
 	 * @since 29.0.0 Types 'federated_group', 'federated_team', 'team' and 'federated_user' are supported
 	 * @since 23.0.0 Type 'group' is supported
+	 * @since 21.0.1 Sort returned results by 
 	 * @since 17.0.0 Type 'guest' is supported
 	 * @since 11.0.0
 	 */