[Question] How do you backup your readonly subvolumes?

As `btrbk` simply ignores the readonly subvolumes, we are unable to backup the manually created readonly subvolumes within the `rootfs`. How do you manage your readonly snapshots?

I recently needed to roll back to one of my backups and I just forget that fact, so I ended up loosing my readonly snapshots. This experience taught me that I need to properly automate the readonly snapshot backup and restore procedure and I'm wondering if there is an existing way for this task.