Smart defaults based on lang?

[jdutant]

Should we use the lang attribute to set up smart defaults, for instance a first-line indent even below headings in French?

(If implementing this, check that the lang attribute is the same in Quarto and Pandoc.)

I don't know if there are strong enough language-specific traditions here. According to this coursebook, p.42-43 both the German typographer Tschichold (french transl. Livre et typographie, Essais choisis, Paris, Éditions Allia, 1998 p.127) and the French typographer Perrousseaux (Mise en pages et impression. Notions élémentaires, Atelier
Perrousseaux éditeur, p. 108-109.