In fact it doesn't support Linux Mint, I have been with it 2 to 3 years believing it was my local DNS but in fact my DNS were those in the ISP box ... so the default installation process is total shit now since 2019 LM 19, and even the process described for ubuntu on the Unbound website has as result you lose your intenet connection ... so you must disable systemd-resolved to use it, find a tutorial for this
I'm using it on my Raspberry Pi for my local network and it works really great!!!