Examine source code of New Tabber

{
  "manifest_version": 2,
  "name": "New Tabber",
  "version": "1.0",
  "description": "Automatically open links in a new tab",
  "homepage_url": "https://gitlab.com/mit-open-source-projects/firefox-extensions/new-tabber",
  "icons": {
    "64": "icons/logo-64.png"
  },
  "permissions": [
    "activeTab"
  ],
  "browser_action": {
    "default_icon": {
      "16": "icons/on3-16.png",
      "32": "icons/on3-32.png"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "new-tabber.js"
      ]
    }
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  }
}