Examine source code of RapidYouTube

{
  "manifest_version": 2,
  "name": "RapidYouTube",
  "version": "1.0",
  "description": "Allow setting a costum speed in YouTube",
  "homepage_url": "https://github.com/SorerBOT/RapidYouTube",
  "icons": {
    "48": "icons/speed-svgrepo-com.svg"
  },
  "permissions": [
    "activeTab"
  ],
  "browser_action": {
    "default_icon": "icons/speed-svgrepo-com.svg",
    "default_title": "RapidYouTube",
    "default_popup": "popup/popup.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{1c7c441a-ad8c-4333-a913-5c4e74f64dcc}"
    }
  }
}