None - because === does not coerce types. Type coercion, not double-equal weirdness as such, is the gripe of the GGP. Non-transitive, inconsistent equality is nothing more than a symptom of JS's rules for implicit conversions.

Language-war disclaimer: I love javascript and everything, it's a very expressive language; but a good wodge of the tooling around it nowadays is to help people avoid things like implicit type-coercion 'surprises'.