The Codeforces team is constantly improving both the software and the hardware parts of the system to make the platform more stable and your time on it comfortable.
However, some types of work can not be carried out without downtime. On February 26, extensive server maintenance is planned, so Codeforces and Polygon may work intermittently from 9:00 UTC to 15:00 UTC. We will try to make the downtime as short as possible, but we cannot completely get rid of it.
We apologize for any potential inconvenience.