My personal Jupyter Notebook settings.` ~/.jupyter/nbconfig/notebook.json`

notebook.json

{
  "toc2": {
    "number_sections": false,
    "skip_h1_title": false,
    "toc_cell": false
  },
  "load_extensions": {
    "plotlywidget/extension": true,
    "jupyter-js-widgets/extension": true,
    "contrib_nbextensions_help_item/main": true,
    "nbextensions_configurator/config_menu/main": true,
    "toc2/main": true
  },
  "Notebook": {
    "Toolbar": false,
    "Header": false
  },
  "keys": {
    "command": {
      "unbind": [
        "up",
        "k",
        "c"
      ],
      "bind": {
        "shift-t,shift-t": "jupyter-notebook:toggle-toolbar",
        "shift-t,shift-h": "jupyter-notebook:toggle-header",
        "k,c,k,c,l": "jupyter-notebook:clear-cell-output",
        "c,c,c": "jupyter-notebook:clear-cell-output",
        "c,c": "jupyter-notebook:clear-cell-output",
        "command-shift-up": "jupyter-notebook:move-cell-up",
        "ctrl-shift-down": "jupyter-notebook:move-cell-down",
        "command-shift-down": "jupyter-notebook:move-cell-down",
        "up": "jupyter-notebook:select-previous-cell",
        "ctrl-shift-up": "jupyter-notebook:move-cell-up",
        "shift-t,shift-m": "jupyter-notebook:toggle-menubar"
      }
    }
  },
  "Cell": {
    "cm_config": {
      "lineNumbers": true
    }
  }
}