Examine source code of Fix Pink Youtube

{
  "name": "Fix Pink Youtube",
  "version": "26.4.20.1015",
  "description": "Fixes pink youtube progress bar and more to red",
  "homepage_url": "https://github.com/GREEB/fix-pink-youtube",
  "manifest_version": 3,
  "minimum_chrome_version": "121",
  "browser_specific_settings": {
    "gecko": {
      "id": "{a0b675fe-bfff-4223-a597-6d4099e8c4b2}",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      },
      "strict_min_version": "58.0"
    }
  },
  "icons": {
    "128": "icon.5cfe5d46.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.youtube.com/*",
        "https://www.youtube-nocookie.com/embed/*"
      ],
      "css": [
        "content.c89544ae.css"
      ],
      "run_at": "document_start",
      "all_frames": true,
      "js": []
    }
  ]
}