AppFlowy/frontend/app_flowy/packages/flowy_editor/example/assets/document.json

{
    "document": {
      "type": "text",
      "attributes": {
        "content": "TITLE"
      },
      "children": [
        {
          "type": "text",
          "attributes": {
            "text-type": "heading1",
            "font-size": 30,
            "content": "aaaaaaaaaaaaaaaaaaaaaaaa"
          }
        },
        {
          "type": "text",
          "attributes": {
            "text-type": "heading1",
            "font-size": 30,
            "content": "bbbbbbbbbbbbbbbbbbbbbbb"
          }
        },
        {
          "type": "text",
          "attributes": {
            "text-type": "heading1",
            "font-size": 30,
            "content": "cccccccccccccccccccccc"
          }
        }
      ]
    }
  }