Examine source code of Chess.com rating hider

{
  "description": "Hides the rating of both the opponent and yourself on chess.com",
  "manifest_version": 2,
  "name": "Chess.com rating hider",
  "version": "1.0",
  "homepage_url": "https://github.com/SturlaSolheim/Hide-chess.com-rating",
  "icons": {
    "48": "icons/logo.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.chess.com/*"
      ],
      "css": [
        "style.css"
      ]
    }
  ]
}