The onboarding component is displayed in the same way as a modal, on top of everything else. It may contain HTML content or simply a lottie to tell the user what they have just unlocked.
TWIG component : Universes/_common/_webapp/_twig/_components/_onboarding.twig
CSS component : Universes/_turf/_common/_css/_components/_onboarding/_onboarding_boosted_markets.scss