Examine source code of Single Tab

{
  "manifest_version": 2,
  "name": "__MSG_extensionName__",
  "description": "__MSG_extensionDescription__",
  "homepage_url": "https://github.com/kdrvs/SingleTab",
  "version": "1.1.5",
  "icons": {
    "16": "icons/16.png",
    "32": "icons/32.png",
    "48": "icons/48.png",
    "128": "icons/128.png"
  },
  "permissions": [
    "tabs",
    "activeTab",
    "storage",
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_title": "Single Tab",
    "default_popup": "popup.html"
  },
  "applications": {
    "gecko": {
      "id": "SingleTab@kdrvs",
      "strict_min_version": "63.0"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "*://*/*"
      ],
      "js": [
        "main.js"
      ]
    }
  ],
  "default_locale": "en"
}