Examine source code of DisCall

{
  "manifest_version": 2,
  "name": "DisCall",
  "version": "1.1resigned1",
  "description": "Discord caller",
  "icons": {
    "16": "icon/icon16.png",
    "48": "icon/icon48.png",
    "128": "icon/icon128.png"
  },
  "permissions": [
    "activeTab",
    "contextMenus"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_icon": {
      "16": "icon/icon16.png",
      "48": "icon/icon48.png",
      "128": "icon/icon128.png"
    },
    "default_title": "DisCall"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{ce130e23-37d2-49f6-a6d6-d2897185c790}"
    }
  }
}