Examine source code of Remove tweet view count

{
  "name": "Remove tweet view count",
  "version": "1.0",
  "description": "Removes the view count under all tweets",
  "homepage_url": "http://github.com/murilocarrijosilva/",
  "manifest_version": 2,
  "icons": {
    "48": "icons/48.png"
  },
  "permissions": [
    "tabs",
    "storage"
  ],
  "content_scripts": [
    {
      "matches": [
        "*://*.twitter.com/*"
      ],
      "all_frames": true,
      "run_at": "document_start",
      "css": [
        "remove_tweet_view_count.css"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "remove-tweet-view-count@murilocarrijosilva.com"
    }
  }
}