Examine source code of webtoon-dark-theme

{
  "manifest_version": 2,
  "name": "MyEyes",
  "version": "1.0",
  "description": "Turns the blinding white color of the Webtoon background to #1E1E1F",
  "icons": {
    "32": "icons/border-32.png",
    "48": "icons/border-48.png",
    "96": "icons/border-96.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.webtoons.com/*/viewer?*"
      ],
      "js": [
        "MyEyes.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{1b9c9294-8094-49c3-8df8-0ebae2da0458}"
    }
  }
}