IPv6 is a building block of the internet, ok, but you have still to implement IPv6 in Dialogs, Checks, etc.Notepad is only a application which uses system default file save/open/etc dialog. If we would only save from local application to a fileshare it's easy to implement via Windows API, but this doesn't work for a backup application. We have our own services which needs to speak IPv6 with vCenter, ESX, WAN Accelerator,Tape Server, Backup Proxy, Backup Repository, etc. For all of this you need to integrate IPv6 into the dialogs and after all of this you need to test everything.
System Engineer @ Veeam Software
NetApp NCIE-SAN for 7-Mode and Clustered Ontap