message: doc: enumerable props
diff: @@ -43,8 +43,9 @@ export class Rpc {
  this.sendMessage({ seqNum, exception: 'error' })
  return
  }
  - /* Somehow certain properties (such as `ex.message`) disappear along the way
  - * through `Webview.postMessage` but make it through in a new object. */
  + /* Certain properties (such as `ex.message`) are not /enumerable/ per ECMAScript
  + * and disappear along the way through `Webview.postMessage`; we create a new object
  + * so that they make it through. */
  const exOut: any = {}
  for (const p of Object.getOwnPropertyNames(ex)) { exOut[p] = ex[p] }
  this.sendMessage({ seqNum, exception: exOut })
  