Examine source code of Date+1

{
  "description": "Ecrit la date du lendemain dans la zone de texte en cours",
  "manifest_version": 2,
  "name": "Date+1",
  "version": "0.0.0.1",
  "homepage_url": "https://github.com/timferrari43/Date-1",
  "icons": {
    "48": "icons/icon48.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "permissions": [
    "activeTab"
  ],
  "browser_action": {
    "default_icon": {
      "16": "icons/icon16.png",
      "32": "icons/icon32.png"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{8a5efcfd-ac9d-4c9e-abec-59ce1213279e}"
    }
  }
}