Examine source code of YouTube Gradient Remover

{
  "manifest_version": 2,
  "name": "YouTube Gradient Remover",
  "version": "1.0.0",
  "description": "Removes the stupid gradient in the background of youtube videos",
  "icons": {
    "48": "./icon.svg"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.youtube.com/watch?*"
      ],
      "js": [
        "./convert.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{8e5bbbe5-032a-459e-a8f0-b1bef605cccd}"
    }
  }
}