isRequired property in Adaptive Cards not working with Botframework Emulator

i'm trying to put "isRequired" property in JSON code to create attachment with Adaptive Card which is display on Botframework Emulator and it's not working.

{
  "type": "AdaptiveCard",
  "body": [
    {
      "type": "TextBlock",
      "size": "Medium",
      "weight": "Bolder",
      "text": "Create List"
    },
    {
      "type": "Input.Text",
      "placeholder": "Restaurant Name",
      "id": "restaurantInput",
      "isRequired":  true
    },
    {
      "type": "Input.Time",
      "id": "timeInput",
      "isRequired": true
    },
    {
      "type": "ActionSet",
      "actions": [
        {
          "type": "Action.Submit",
          "title": "Create"
        }
      ]
    }
  ],
  "$schema": "http://adaptivecards.io/schemas/adaptive-card.json",
  "version": "1.3"
}

messagebox after add "isRequired" property (empty) https://i.stack.imgur.com/wWt5S.png

messagebox without "isRequired" property https://i.stack.imgur.com/myJrq.png

Any advice?