Examine source code of Search image

{
  "manifest_version": 2,
  "name": "Search image",
  "description": "Select some text, right-click and choose \"Search image\" in the menu, a new tab will open with the searched text.",
  "version": "0.1.4resigned1",
  "icons": {
    "48": "Search-Images-icon48.png"
  },
  "permissions": [
    "tabs",
    "contextMenus",
    "http://*/*",
    "https://*/*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "searchimage@searchimage.fr"
    }
  }
}