The link for adding descriptions to triggers created by low-level discovery has been removed from Monitoring → Triggers. Such descriptions were later deleted anyway by low-level discovery, if they were not present in the original trigger prototype.
Active agent auto-registration events are not generated any more if there is no action for auto registration.
Zabbix server and frontend now try to set the MySQL autocommit variable to "autocommit=1" (enable MySQL autocommit mode) at the beginning of each connection to the database. Failing to do so results in failed database connection.