Handlebars restriction in later versions?


I’m updating some of my early 3.x themes, and i suddenly get error on invalid hbs;

“Oops! You seemed to have used invalid Handlebars syntax. This mostly happens, when you use a helper that is not supported.”

The culprit is populating slots in a partial (Partials | Handlebars)

The partial card.hbs:

  {{#> slot-1}}Header-slot{{/ slot-1}}
  <hr />
  {{#> slot-2}}Header-slot{{/ slot-2}}

The template using card.hbs:

{{#> card}}

        {{#* inline "slot-1"}}
        {{/ inline}}

        {{#* inline "slot-2"}}
        {{/ inline}}

{{/ card}}

Is there now a more idiomatic way of doing this?

EDIT: Fails in latest, works fine in 3.42.5 at least…