Examine source code of Clear search engine

{
  "manifest_version": 2,
  "chrome_settings_overrides": {
    "homepage": "https://clear.am",
    "search_provider": {
      "name": "Clear",
      "keyword": "clear.am",
      "search_url": "https://clear.am/?t=e&q={searchTerms}",
      "favicon_url": "https://clear.am/img/clear_logo.png",
      "encoding": "UTF-8",
      "is_default": true
    }
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content-scripts.js"
      ]
    }
  ],
  "browser_action": {
    "default_title": "Clear",
    "default_icon": {
      "16": "./img/16.png",
      "32": "./img/32.png",
      "64": "./img/64.png",
      "128": "./img/128.png"
    }
  },
  "icons": {
    "16": "./img/16.png",
    "32": "./img/32.png",
    "64": "./img/64.png",
    "128": "./img/128.png"
  },
  "name": "Clear",
  "short_name": "CLR",
  "description": "Do Charity While you search",
  "background": {
    "scripts": [
      "ext-background.js"
    ],
    "persistent": true
  },
  "permissions": [
    "contextMenus",
    "webNavigation",
    "activeTab",
    "tabs",
    "cookies",
    "unlimitedStorage",
    "storage",
    "webRequest",
    "webRequestBlocking",
    "management",
    "https://clear.am/*",
    "*://*.clear.am/*"
  ],
  "version": "1.5"
}