Array message shown…?

Hi,
See here https://prntscr.com/l3y8u3
Is it normal? Never seen before.
The job finished apparently without errors and the string about the array disappeared.
Should I consider the backup as good?
Thanks

Here the log:
[INFO] BackWPup 3.6.1; A project of Inpsyde GmbH
[INFO] WordPress 4.9.8 on https://www.georgsoltiaccademia.org/wp/
[INFO] Log Level: Normal
[INFO] BackWPup job: GSA_backup
[INFO] Logfile is: backwpup_log_aae806_2018-10-09_10-48-22.html
[INFO] Backup file is: backwpup_R2VOQBT201_solti_2018-10-09.zip
[09-Oct-2018 10:48:22] 1. Try to backup database …
[09-Oct-2018 10:48:22] Connected to database solti_db on localhost
[09-Oct-2018 10:48:25] Added database dump “solti_db.sql” with 12.32 MB to backup file list
[09-Oct-2018 10:48:25] Database backup done!
[09-Oct-2018 10:48:25] 1. Trying to make a list of folders to back up …
[09-Oct-2018 10:48:38] Added “wp-config.php” to backup file list
[09-Oct-2018 10:48:38] 1578 folders to backup.
[09-Oct-2018 10:48:38] 1. Trying to generate a file with installed plugin names …
[09-Oct-2018 10:48:38] Added plugin list file “GEORG-SOLTI-ACCADEMIA.pluginlist.2018-10-09.txt” with 3.65 KB to backup file list.
[09-Oct-2018 10:48:38] 1. Trying to generate a manifest file …
[09-Oct-2018 10:48:38] Added manifest.json file with 7.52 KB to backup file list.
[09-Oct-2018 10:48:39] 1. Trying to create backup archive …
[09-Oct-2018 10:48:39] Compressing files as ZipArchive. Please be patient, this may take a moment.
[09-Oct-2018 10:48:39] Array ( [0] => /var/www/vhosts/georgsoltiaccademia.org/httpdocs/wp/wp-content/uploads/backwpup-aae806-temp/solti_db.sql [1] => /var/www/vhosts/georgsoltiaccademia.org/httpdocs/wp/wp-config.php [2] => /var/www/vhosts/georgsoltiaccademia.org/httpdocs/wp/wp-content/uploads/backwpup-aae806-temp/GEORG-SOLTI-ACCADEMIA.pluginlist.2018-10-09.txt [3] => /var/www/vhosts/georgsoltiaccademia.org/httpdocs/wp/wp-content/uploads/backwpup-aae806-temp/manifest.json [4] => /var/www/vhosts/georgsoltiaccademia.org/httpdocs/wp/wp-content/uploads/backwpup-aae806-temp/backwpup_readme.txt )
[09-Oct-2018 10:58:39] Backup archive created.
[09-Oct-2018 10:58:39] Archive size is 351.73 MB.
[09-Oct-2018 10:58:39] 14425 Files with 452.72 MB in Archive.
[09-Oct-2018 10:58:40] 1. Try to send backup file to Dropbox …
[09-Oct-2018 10:58:40] Authenticated with Dropbox of user: Drauth.org Località San Valeriano 6 – 01011 Canino – p.i. 02264640489
[09-Oct-2018 10:58:40] Uploading to Dropbox …
[09-Oct-2018 10:58:40] Beginning new file upload session
[09-Oct-2018 11:01:32] Finishing upload session with a total of 352 MB uploaded
[09-Oct-2018 11:01:35] Backup transferred to /solti/backwpup_R2VOQBT201_solti_2018-10-09.zip
[09-Oct-2018 11:01:36] One file deleted from Dropbox
[09-Oct-2018 11:01:36] One old log deleted
[09-Oct-2018 11:01:36] Job done in 794 seconds.

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