Backups fail after the update to Plesk Obsidian 18.0.47: The backup process fail

[Administrator]

Symptoms
Backups in Plesk - including scheduled backups - can not be created with:

Error: The backup process failed: can't concat str to bytes

Plesk Obsidian has been recently updated to version 18.0.47.
Cause

Product issue:

#PPPM-13733 "Creation of a domain backup no longer fails when the "Exclude log files" or "Exclude specific files from the backup" options are enabled."
Fixed in:
Plesk Obsidian 29 September 2022 (Linux)
Resolution
Please consider updating your server:
How to install Plesk updates