Examine source code of Expando2

{
  "manifest_version": 2,
  "name": "Expando",
  "version": "1.3resigned1",
  "description": "Expands image and video previews from subreddits, and deletes everything else.",
  "content_scripts": [
    {
      "matches": [
        "*://*.reddit.com/*"
      ],
      "js": [
        "notext.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{8852a459-e42e-4ea2-9d1e-eb360482ea6a}"
    }
  }
}