Examine source code of Crunchyroll Dimming

{
  "manifest_version": 2,
  "version": "0.0.1",
  "name": "Crunchyroll Dimming",
  "description": "Remove screen dimming effect in Crunchyroll",
  "permissions": [
    "https://*.crunchyroll.com/*"
  ],
  "content_scripts": [
    {
      "matches": [
        "https://static.crunchyroll.com/vilos-v2/web/vilos/player.html*"
      ],
      "css": [
        "player.css"
      ],
      "all_frames": true,
      "run_at": "document_start"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{ce689e15-9b2d-4c2c-93ec-d45a79ab237b}"
    }
  }
}