Warning: Trying to access array offset on value of type null in LBKBaseComponent class

When we are trying to add Custom text for LBK Tab then we are getting error for "The database connection is not serializable".

LogicException: The database connection is not serializable. This probably means you are serializing an object that has an indirect reference to the database connection. Adjust your code so that is not necessary. Alternatively, look at DependencySerializationTrait as a temporary solution. in Drupal\Core\Database\Connection->__sleep() (line 2030 of /var/www/docroot/core/lib/Drupal/Core/Database/Connection.php).