`BufferSource` is from web IDL (`lib.dom.d.ts`), which is not always imported. `ArrayBuffer` and `ArrayBufferView` are from the ES spec (`lib.es*.d.ts`) so they should always be available.
* @typedef {Object} MakePostRequestOptions
* @property {Record<string,string|null>} [headers] Headers to set on the request. Set a property to
* `null` to *delete* that header.
- * @property {BufferSource|null} [prf] `prf` buffer to pass on the request body.
+ * @property {ArrayBuffer|ArrayBufferView<ArrayBuffer>|null} [prf] `prf` buffer to pass on the request body.
*/
/**