Examine source code of Pepper Grid

{
  "name": "Pepper Grid",
  "description": "Brings back the best grid layout for Pepper websites. Report issues on pepper@coust.cloud.",
  "version": "1.0.5",
  "manifest_version": 2,
  "default_locale": "en",
  "content_scripts": [
    {
      "matches": [
        "*://*.pepper.pl/*",
        "*://*.promodescuentos.com/*",
        "*://*.pelando.com.br/*",
        "*://*.hotukdeals.com/*",
        "*://*.dealabs.com/*",
        "*://*.nl.pepper.com/*",
        "*://*.mydealz.de/*",
        "*://*.preisjaeger.at/*",
        "*://*.desidime.com/*",
        "*://*.chollometro.com/*",
        "*://*.pepper.ru/*",
        "*://*.pepper.it/*"
      ],
      "js": [],
      "css": [
        "styles/grid.css"
      ],
      "run_at": "document_start"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "pepper@coust.cloud"
    }
  }
}