DEPRECATED: Invalid characters passed for attempted conversion…

Just installed this morning!
Here’s log for the first run, some warnings – what does the “Deprecated” message mean please?

Thanks!
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[INFO] BackWPup 3.7.1; A project of Inpsyde GmbH
[INFO] WordPress 5.4.2 on https://www.3ls.uk/
[INFO] Log Level: Normal (translated)
[INFO] BackWPup job: 3ls
[INFO] Logfile is: backwpup_log_a74d4a_2020-09-21_10-30-38.html
[INFO] Backup file is: 2020-09-21_10-30-38_HKIJHUM501.zip
[21-Sep-2020 10:30:38] 1. Try to backup database …
[21-Sep-2020 10:30:38] Connected to database dbs41199 on db5000046259.hosting-data.io
[21-Sep-2020 10:30:40] Added database dump “dbs41199.sql” with 20.72 MB to backup file list
[21-Sep-2020 10:30:40] Database backup done!
[21-Sep-2020 10:30:40] 1. Trying to make a list of folders to back up …
[21-Sep-2020 10:30:40] Added “wp-config.php” to backup file list
[21-Sep-2020 10:30:40] 1074 folders to backup.
[21-Sep-2020 10:30:40] 1. Trying to create a WordPress export to XML file …
[21-Sep-2020 10:30:42] Check WP Export file …
[21-Sep-2020 10:30:42] WP Export file is a valid WXR file.
[21-Sep-2020 10:30:42] Added XML export “3ls.Y-m-d.xml” with 2.78 MB to backup file list.
[21-Sep-2020 10:30:42] 1. Trying to generate a file with installed plugin names …
[21-Sep-2020 10:30:42] Added plugin list file “Expert-language-translation-simply.pluginlist.2020-09-21.txt” with 3.38 KB to backup file list.
[21-Sep-2020 10:30:42] 1. Trying to generate a manifest file …
[21-Sep-2020 10:30:42] Added manifest.json file with 4.49 KB to backup file list.
[21-Sep-2020 10:30:42] 1. Trying to create backup archive …
[21-Sep-2020 10:30:42] Compressing files as ZipArchive. Please be patient, this may take a moment.
[21-Sep-2020 10:35:51] WARNING: Job restarts due to inactivity for more than 5 minutes.
[21-Sep-2020 10:35:51] 2. Trying to create backup archive …
[21-Sep-2020 10:37:58] Backup archive created.
[21-Sep-2020 10:37:58] Archive size is 1.01 GB.
[21-Sep-2020 10:37:58] 10132 Files with 1.13 GB in Archive.
[21-Sep-2020 10:37:59] DEPRECATED: Invalid characters passed for attempted conversion, these have been ignored
[21-Sep-2020 10:37:59] DEPRECATED: Invalid characters passed for attempted conversion, these have been ignored
[21-Sep-2020 10:37:59] DEPRECATED: Invalid characters passed for attempted conversion, these have been ignored
[21-Sep-2020 10:37:59] DEPRECATED: Invalid characters passed for attempted conversion, these have been ignored
[21-Sep-2020 10:37:59] DEPRECATED: Invalid characters passed for attempted conversion, these have been ignored
[21-Sep-2020 10:37:59] DEPRECATED: Invalid characters passed for attempted conversion, these have been ignored
[21-Sep-2020 10:37:59] DEPRECATED: Invalid characters passed for attempted conversion, these have been ignored
[21-Sep-2020 10:37:59] 1. Trying to check database …
[21-Sep-2020 10:38:00] Database check done!
[21-Sep-2020 10:38:00] WARNING: Job finished with warnings in 442 seconds. Please resolve them for correct execution.

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