If I add an empty root declaration to my CSS file like this

root {

}

I get this warning

WARNING: com.sun.javafx.css.parser.CSSParser declaration Expected IDENT at file:/C:/Users/Randahl/Dropbox/Development/wefend/ui/target/classes/styling/wefend.css[16,2]

where the location 16,2 is actually right after the ending curly bracket.

I think this warning must be wrong - as far as I know, there is no requirement in CSS to not have empty declarations.