Examine source code of ARTE speed

{
  "manifest_version": 2,
  "name": "ARTE speed",
  "version": "0.1.0",
  "description": "Adds a speed slider to the ARTE video player.",
  "icons": {
    "48": "icon.svg",
    "96": "icon.svg"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.arte.tv/*"
      ],
      "js": [
        "main.js"
      ]
    }
  ]
}