[Existing feature] Add note to manual backup

It would be super helpful to be able to add a short note when making a manual backup. At the moment I am trying to find something and I have to go through every single backup. At the very least it would be helpful to know which backups were generated manually, but ideally to be able to a note like “Backup before migration”, “Backup before updating plugin” or whatever. This seems like a relatively easy add but it would be really really helpful! Thanks!