Examine source code of Local Masto Redirect

{
  "manifest_version": 2,
  "name": "Local Masto Redirect",
  "version": "1.1",
  "description": "Adds a button that will redirect you to your local masto-instance version of this post.",
  "icons": {
    "64": "icons/fediverse_64.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*/@*/*",
        "*://*/notes/*",
        "*://*/notice/*"
      ],
      "js": [
        "inject.js"
      ]
    }
  ],
  "options_ui": {
    "page": "options.html"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "page_action": {
    "default_icon": "icons/fediverse_64.png",
    "default_title": "Open in local mastodon instance!"
  },
  "permissions": [
    "activeTab",
    "storage",
    "<all_urls>"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "localmastoredirect@teascade.net"
    }
  }
}