To add some details: this is actually a misconfiguration on the MySQL server part, albeit a very frequent one.
Here, MySQL is configured with a server timezone of "CEST".
However, "CEST" (Central European Summer Time) is not a valid "timezone", it's merely an offset to UTC, but it's only valid during the summer. On the other hand, "Europe/Paris" is a valid timezone, which knows when it means "UTC+1" and when it means "UTC+2".
MySQL has several legacy timezone handling modes. DSS uses the modern timezone handling, which properly knows that CEST is not a valid timezone.