Content mount problem for single-language "multilingual" site

support
7

To simplify:

git clone --single-branch -b hugo-forum-topic-37215 https://github.com/jmooring/hugo-testing hugo-forum-topic-37215
cd hugo-forum-topic-37215
hugo && tree public/

Result:

public/
├── post/
│   ├── test/
│   │   └── index.html
│   └── index.html
└── index.html

Now add this to config.toml:

[[module.mounts]]
source = "content"
target = "content"

And then this:

rm -rf public/ && hugo && tree public/

Produces this:

public/
├── foo/
│   ├── post/
│   │   └── test/
│   │       └── index.html
│   └── index.html
└── index.html

See https://gohugo.io/hugo-modules/configuration/#module-config-mounts

When the mounts config was introduced in Hugo 0.56.0, we were careful to preserve the existing staticDir and similar configuration to make sure all existing sites just continued to work. But you should not have both: if you add a mounts section you should remove the old staticDir etc. settings.