Examine source code of Refined GitLab

{
  "manifest_version": 2,
  "name": "Refined GitLab",
  "version": "0.9.1",
  "description": "🏷 Make your GitLab experience better!",
  "homepage_url": "https://gitlab.com/kiprasmel/refined-gitlab",
  "minimum_chrome_version": "74",
  "applications": {
    "gecko": {
      "id": "refined-gitlab@kipras.org",
      "strict_min_version": "67.0"
    }
  },
  "icons": {
    "48": "refined-gitlab.png",
    "96": "refined-gitlab@2x.png"
  },
  "permissions": [
    "cookies",
    "tabs",
    "<all_urls>"
  ],
  "options_ui": {
    "chrome_style": true,
    "page": "options.html"
  },
  "background": {
    "scripts": [
      "browser-polyfill.min.js",
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "browser-polyfill.min.js",
        "content.js"
      ]
    }
  ]
}