styleenv/share/jupyter/lab/schemas/@jupyter-notebook/application-extension/shell.json

{
  "$schema": "http://json-schema.org/draft-07/schema",
  "title": "Notebook Shell",
  "description": "Notebook Shell layout settings.",
  "properties": {
    "layout": {
      "$ref": "#/definitions/layout",
      "type": "object",
      "title": "Customize shell widget positioning",
      "description": "Overrides default widget position in the application layout",
      "default": {
        "Markdown Preview": { "area": "right" }
      }
    }
  },
  "additionalProperties": false,
  "type": "object",
  "definitions": {
    "layout": {
      "type": "object",
      "properties": {
        "[\\w-]+": {
          "type": "object",
          "properties": {
            "area": {
              "enum": ["left", "right"]
            }
          },
          "additionalProperties": false
        }
      }
    }
  }
}