Examine source code of SteamRep Checker

{
  "manifest_version": 2,
  "name": "SteamRep Checker",
  "short_name": "SR Checker",
  "version": "0.8.1",
  "description": "This extension checks the reputation of a Steam user on SteamRep.",
  "icons": {
    "16": "ext_icons/icon16.png",
    "32": "ext_icons/icon32.png",
    "48": "ext_icons/icon48.png",
    "64": "ext_icons/icon64.png",
    "128": "ext_icons/icon128.png"
  },
  "author": "Nasreddine Houria <nasreddine.houria@gmail.com>",
  "content_scripts": [
    {
      "matches": [
        "*://steamcommunity.com/id/*",
        "*://steamcommunity.com/profiles/*"
      ],
      "css": [
        "content_script/css/styles.css"
      ],
      "js": [
        "content_script/js/checker.js"
      ]
    }
  ],
  "homepage_url": "https://github.com/0xffffabcd/steamrep-checker",
  "permissions": [
    "activeTab",
    "*://steamcommunity.com/*",
    "*://steamrep.com/*",
    "*://forums.steamrep.com/*"
  ],
  "web_accessible_resources": [
    "icons/*"
  ],
  "background": {
    "scripts": [
      "content_script/eventPage.js"
    ]
  }
}