Examine source code of Tab2JSON

{
  "name": "Tab2JSON",
  "description": "This extension allows you to close tabs and store them as json files",
  "manifest_version": 2,
  "version": "0.1.0",
  "icons": {
    "48": "icons/icon.svg",
    "96": "icons/icon.svg"
  },
  "permissions": [
    "tabs",
    "<all_urls>",
    "downloads"
  ],
  "browser_action": {
    "default_icon": "icons/icon.svg",
    "default_title": "Tab2JSON"
  },
  "background": {
    "scripts": [
      "tab2json.js"
    ]
  },
  "commands": {
    "savetab": {
      "suggested_key": {
        "default": "Ctrl+Shift+Insert"
      },
      "description": "saves the current tab"
    },
    "thistab": {
      "suggested_key": {
        "default": "Ctrl+Shift+Down"
      },
      "description": "saves the current tab and closes it"
    },
    "nexttab": {
      "suggested_key": {
        "default": "Ctrl+Shift+Right"
      },
      "description": "switches to the next tab"
    },
    "prevtab": {
      "suggested_key": {
        "default": "Ctrl+Shift+Left"
      },
      "description": "switches to the previous tab"
    },
    "closetab": {
      "suggested_key": {
        "default": "Ctrl+Shift+Up"
      },
      "description": "closes the current tab"
    },
    "alltabs": {
      "suggested_key": {
        "default": "Alt+Shift+P"
      },
      "description": "saves all tabs of the current window which are not pinned and closes them"
    }
  }
}