Evergreen version: all
The "Require at least one address for Patron Registration" prevents a user from clicking the "x" to remove the patron address fields at registration, but does not prevent staff from removing all patron addresses later when editing the patron record.
We would like to broaden this setting so that it applies when the patron record is edited, making it consistent with other required fields for patron registration. If there are use cases where a site may want to require an address at registration, but not when editing the patron record, then maybe we can add another setting, but my preference would be to just have one setting to cover both situations. Since there is a way to mark an address as invalid, I can't think of any use cases off the top of my head.
There are times that accounts intentionally don't have addresses and new addresses shouldn't be added, but use of the client may still be desired for editing them. Generic accounts for various purposes (whether it be staff use, vendor, or selfcheck type activities) are an example at MVLC.
To cover that case, I propose a different setting as a solution: Require address if account had an address. If the account had no addresses when loaded you don't need to add one to edit, but if it had at least one you can't save it with none while the setting is active.