Setup

To avoid configuring dnsmasq directly, you can use NetworkManager’s plugin to enable support for its own instance (?) of dnsmasq.

# edit /etc/NetworkManager/NetworkManager.conf
[main]
dns=dnsmasq

sudo systemctl restart NetworkManager.service

Then you can edit configuration. Example here adds wildcard redirect for *.hello.test (so foo.hello.test will resolve to localhost).

# /etc/NetworkManager/dnsmasq.d/redirect.conf
address=/.hello.test/127.0.0.1