Error

{# I'd like to use ``build.error|urlize`` here, so we can have nice links. However, this is not possible because we are using `data-bind="text: error"` which means that Knockout.js will use the `.error` attribute to fill the content of this tag dynamically. #} The configuration key "build.os" is required to build your documentation. Read more at https://docs.readthedocs.io/en/stable/config-file/v2.html#build-os