I used these steps when attempting to reproduce your issue. But I could not reproduce it.
- Install Hugo 0.48
hugo new site example.com
cd example.com
git init
git submodule add https://github.com/budparr/gohugo-theme-ananke.git themes/ananke
- Open
config.toml
and add linetheme = "ananke"
hugo new posts/my-first-post.md
hugo server -D
- Open
config.toml
and edit linetitle = "My New Hugo Site"
to betitle = "My New Hugo SiteZ"