Examine source code of RockStart

{
  "manifest_version" : 3 ,
  "name" : "RockStart",
  "description" : "A calm new tab page: Arc-style bookmarks sidebar, live tabs, flip clock, synced to-dos, GitHub PRs and issues, and wallpapers.",
  "version" : "0.2.6",
  "icons" : {
    "16" : "icons/icon-16.png",
    "32" : "icons/icon-32.png",
    "48" : "icons/icon-48.png",
    "128" : "icons/icon-128.png"
  },
  "permissions" : [
    "storage" ,
    "tabs" ,
    "search" ,
    "bookmarks" ,
    "topSites" 
  ],
  "host_permissions" : [
    "https://www.bing.com/*" ,
    "https://picsum.photos/*" ,
    "https://commons.wikimedia.org/*" ,
    "https://en.wikipedia.org/*" ,
    "https://collectionapi.metmuseum.org/*" ,
    "https://api.github.com/*" 
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "rockstart@pearkoder.com",
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    },
    "gecko_android": {
      "strict_min_version": "142.0"
    }
  },
  "chrome_url_overrides" : {
    "newtab" : "newtab.html"
  }
}