Examine source code of Time Stamper

{
  "name": "Time Stamper",
  "short_name": "Time Stamper",
  "version": "0.2.0",
  "manifest_version": 2,
  "description": "Quick and easy adding of a timestamp to an input field",
  "icons": {
    "16": "images/ts-icon_16.png",
    "128": "images/ts-icon_128.png"
  },
  "permissions": [
    "<all_urls>",
    "contextMenus",
    "storage"
  ],
  "background": {
    "page": "background.html"
  },
  "options_ui": {
    "page": "options.html",
    "chrome_style": false
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "all_frames": true
    }
  ],
  "browser_action": {
    "default_icon": {
      "19": "images/ts-icon_19.png"
    },
    "default_title": "Time Stamper Options"
  },
  "web_accessible_resources": [],
  "commands": {
    "insert-timestamp": {
      "suggested_key": {
        "default": "Ctrl+Shift+Y",
        "mac": "Command+Shift+Y"
      },
      "description": "Insert timestamp"
    },
    "applications": {
      "gecko": {
        "id": "{22b54065-a9d5-4f7e-84d5-e488a236959f}",
        "strict_min_version": "48.0"
      }
    }
  }
}