Framing : @type still included although @explicit = true

[tfrancart]

framing excerpt : here I just want the prefLabel key, an no others, so I set ̀ "@explicit": true

    "broader": {
      "@omitDefault": true,
      "@embed": "@always",
      "prefLabel": {},
      "@explicit": true
    },

output

          "broader": {
            "id": "https://rdf.archives-nationales.culture.gouv.fr/activityType/FRAN_RI_011-d5bhviliu0--ghc74xbke76o",
            "type": [
              "Concept",
              "rico:ActivityType"
            ],
            "prefLabel": [
              {
                "@language": "fr",
                "@value": "justice"
              }
            ]
          },

I still get the type key and I cannot get rid of it. Any idea how to remove type from the output ?