Examine source code of HideTheChecks

{
  "manifest_version": 2,
  "name": "HideTheChecks",
  "version": "1.1",
  "description": "Hide posts from any Twitter user with a blue check.",
  "icons": {
    "48": "icons/hidecheck_icon.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.twitter.com/*"
      ],
      "js": [
        "hidechecks.js"
      ]
    }
  ],
  "browser_action": {
    "default_icon": {
      "48": "icons/hidecheck_icon.png"
    },
    "default_title": "HideTheChecks",
    "default_popup": "popup/settings.html"
  },
  "options_ui": {
    "page": "popup/settings.html",
    "browser_style": true
  },
  "permissions": [
    "storage"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "HideTheChecks@gaiablade.com",
      "strict_min_version": "57.0"
    }
  }
}