Allow users to add (dynamic) prefix (e.g. date) to backup filename
Applies to: I'm currently using a paid Dropbox account as an offsite backup, but this is relevant for all (offsite) backups.
What happens: When running full server backups, Plesk currently creates a file called server.domain.tld.tar.
The problem: When scheduling (daily/weekly/monthly) full server backups, the new backup file will have the exact same name as the previous backup file.
The result: When selecting e.g. the 12 latest backups to be saved, Plesk backup manager will display these backups as individual entries, but in reality when using a service like Dropbox to create automated off-site backups, the next backup overwrites the previous backup and relies on the version history feature (if available) of your off-site service. In case of Dropbox this is 30 days for a lot of plans.
In another uservoice entry, Plesk team calls this behavior a feature, as it doesn't count against the storage cap when version history is used. However, the availability of version history is way more restricted (and more expensive) than simple storage space.
Suggested solution: Allow users to add a dynamic prefix/suffix like the creation date of the backup to the file name. This simple change would allow users to choose between:
1. having the dynamic prefix (date) in the file name allowing for longer backup history than the off-site service 'version history' dependency allows for, while taking up more storage space.
2. not having a dynamic prefix (date) in the file name, allowing for the use of the off-site service 'version history' feature.
This way users can pick between less storage used or a longer backup history.
In my personal situation I have 2TB of storage, 20GB full server backups that I run once a month. I want to keep 12 backups for a total of ±240GB of storage. This is well within the boundaries of my storage allocation, but is currently impossible as Plesk is overwriting the file, causing a 30 day expiry of my monthly backups instead.

Thank you for your input. We will consider this functionality in upcoming releases if it is popular. Everyone, please continue voting for this feature if you consider it important.
—
IG