Resolved -
The third-party cookies issue has been resolved. The problem was caused by a recent change, which included an incorrect configuration blocking proper iframe load.
Nov 5, 14:36 UTC
Investigating -
This issue affects only the Monitoring extension in Plesk. 360 Monitoring services, including alerts, work as usual, all monitoring data can be accessed from the 360 Monitoring page directly.
Nov 4, 20:16 UTC