Examine source code of Custom New Tabs

{
  "manifest_version": 2,
  "name": "Custom New Tab",
  "version": "4.8resigned1",
  "homepage_url": "https://github.com/deadmund/Custom-New-Tab/wiki",
  "description": "CNT allows the user to specify any website (URL) to be opened in new tabs by default instead of the about:newtab page.",
  "applications": {
    "gecko": {
      "id": "CNTwe@ednovak.net",
      "strict_min_version": "55.0"
    }
  },
  "permissions": [
    "storage",
    "tabs"
  ],
  "icons": {
    "32": "cnt_icon_32.png",
    "48": "cnt_icon_48.png",
    "64": "cnt_icon_64.png"
  },
  "background": {
    "scripts": [
      "cnt-main-bg-script.js"
    ]
  },
  "options_ui": {
    "page": "prefs.html"
  }
}