Acronis Backup: exclusion of a partition does not work

You use Acronis Backup Cloud version 7.7 or Acronis Backup 12.5 with cloud management.

You create an Entire machine backup plan and select 'Version 12' backup format. In the exclusions, you specify one of the partitions, for example E:, to be excluded from the backup.

The specified partition is not excluded from the backup.