{
  "elmType": "div",
  "style": {
    "width": "100%",
    "display": "=if([$Title] && [$AssignedTo.email], 'block', 'none')",
    "padding-top": "10px",
    "border-top": "1px solid"
  },
  "attributes": {
    "class": "ms-fontColor-neutralSecondary"
  },
  "children": [
    {
      "elmType": "a",
      "attributes": {
        "target": "_blank",
        "href": "='https://teams.microsoft.com/l/chat/0/0?users=' + [$AssignedTo.email] + '&message=This is related to your Task: ' + [$Title]",
        "class": "ms-fontColor-themePrimary"
      },
      "children": [
        {
          "elmType": "span",
          "txtContent": "Chat with Task Owner"
        },
        {
          "elmType": "span",
          "style": {
            "margin-left": "8px",
            "vertical-align": "middle"
          },
          "attributes": {
            "iconName": "TeamsLogo",
            "class": "ms-fontColor-themePrimary ms-fontSize-xl"
          }
        }
      ]
    }
  ]
}