We need to update bobtemplates.plone to include this. Thanks for pointing it out, I opened an issue.
In the meantime you need to do it yourself. Basically you need to register a resource and a bundle for your package, in the file
profile/default/registry.xml, and that resource will reference a copy of barceloneta.plone.less that you'll add in your package's
theme/less folder. You need a copy because in the end of the file you'll add imports to your custom LESS/CSS.
Also you'll need to edit your existing
profile/default/metadata.xml to register all Barceloneta resources (JS and CSS) as proper entries in Site Setup > Resource Registries. That is needed so you can reference those later in your new
It's a bit of indirection but the good news is that you'll be able to turn off specific parts of Barceloneta that may not be useful to your theme.
You can read more about it in https://training.plone.org/5/theming/theme-package.html#css-and-js-resources Let us know if you get stuck.