Where did JsxPPXReactSupport go?

[nojaf]

I'm messing around with React server components and found that:

@react.component
let make = async () => { <p></p> }

leads to

[
  structure_item 
    Pstr_type Nonrec
    [
      type_declaration "props"  
        attribute  "res.jsxComponentProps"
          []
        ptype_params =
          []
        ptype_cstrs =
          []
        ptype_kind =
          Ptype_record
            []
        ptype_private = Public
        ptype_manifest =
          None
    ]
  structure_item 
    Pstr_value Nonrec
    [
      <def>
        pattern 
          Ppat_var "make" 
        expression 
          Pexp_fun
          async
          arity:1
          Nolabel
          None
          pattern 
            Ppat_constraint
            pattern 
              Ppat_any
            core_type 
              Ptyp_constr "props" 
              []
          expression 
            Pexp_apply
            expression 
              Pexp_ident "Primitive_promise.unsafe_async" 
            [
              <arg>
              Nolabel
                expression 
                  attribute  "res.braces"
                    []
                  Pexp_apply
                  expression 
                    Pexp_ident "ReactDOM.jsx" 
                  [
                    <arg>
                    Nolabel
                      expression 
                        Pexp_constant PConst_string("p",None)
                    <arg>
                    Nolabel
                      expression 
                        Pexp_record
                        []
                        None
                  ]
                  transformed_jsx: true
            ]
            transformed_jsx: false
    ]
  structure_item 
    Pstr_value Nonrec
    [
      <def>
        pattern 
          Ppat_var "make" 
        expression 
          Pexp_let Nonrec
          [
            <def>
              pattern 
                Ppat_var "Today" 
              expression 
                Pexp_fun
                arity:1
                Nolabel
                None
                pattern 
                  Ppat_var "props" 
                expression 
                  Pexp_apply
                  expression 
                    Pexp_ident "JsxPPXReactSupport.asyncComponent" 
                  [
                    <arg>
                    Nolabel
                      expression 
                        Pexp_apply
                        expression 
                          Pexp_ident "make" 
                        [
                          <arg>
                          Nolabel
                            expression 
                              Pexp_ident "props" 
                        ]
                        transformed_jsx: false
                  ]
                  transformed_jsx: false
          ]
          expression 
            Pexp_ident "Today" 
    ]
]

(via bunx bsc src/components/Today.res -bs-jsx 4 -dparsetree -only-parse -ignore-parse-errors)

JsxPPXReactSupport is not present in StdLib.
Does anyone know what should happen here?
Can't reproduce in playground, but as @rescript/core is loaded there, it might be present somehow.