I ran npx mkcert create-ca; npx mkcert create-cert, then tried to feed those certs to Nuxt's config: https://nuxt.com/docs/api/configuration/nuxt-config#https
If I run it using ca.key and ca.crt I get this in my browser (Vivaldi)

If I use cert.key and cert.crt, then I get the unsafe warning:

Am I using this output wrong?