Examine source code of MeetMic

{
  "manifest_version": 2,
  "name": "QuickWhisper",
  "version": "1.0",
  "description": "Fast and accurate transcriptions on Mac",
  "icons": {
    "16": "images/icon16_white.png",
    "32": "images/icon32_white.png",
    "48": "images/icon48_white.png",
    "128": "images/icon128_white.png"
  },
  "background": {
    "scripts": [
      "service_worker.js"
    ]
  },
  "browser_action": {
    "default_icon": "images/icon32_white.png",
    "default_title": "Open URL in QuickWhisper"
  },
  "permissions": [
    "contextMenus",
    "tabs"
  ],
  "commands": {
    "XUOpenCurrentSite": {
      "suggested_key": {
        "default": "Ctrl+Shift+T",
        "mac": "MacCtrl+Shift+T"
      },
      "description": "Open URL in QuickWhisper"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "quickwhisper@example.com"
    }
  }
}