Hello, sorry for jumping in randomly but I believe I am running into similar issues that Bcutter is having.
I have Pi-hole running on an Ubuntu VM that is on my UnRAID server. I tried doing the tweak/virtual_interfaces that you told bcutter about but I'm still having issues.
I'm trying to get Unbound up and working, but it seems like something is messed up and it is affecting both Pihole and Unbound possibly. I have uninstalled and reinstalled both Pihole and Unbound.
When I go to click the save button it pops up every time not just when selecting the Upstream DNS Servers.
Should I run a debug and provide that token here?
Thank you very much for any help!