In the default installation placeholders are shown in the layer list instead of localized layer names

[sgiaccio]

[fergonco]

With placeholders do you mean the ${blabla} or the position of the layer placeholder, "Provincias" in the image?

[sgiaccio]

I mean ${blabla}, it's just a matter of adding an entry in the message.properties files

[fergonco]

I think it would be a good practice to group the translations for demo data so that they can be easily identified, like:
#demo data translations
blabla=blablabla

That would be useful if a new language is added because you can safely ignore those keys. And would also a way to close #21 as well.