Examine source code of TwitRestore

{
  "manifest_version": 2,
  "name": "TwitRestore",
  "version": "1.0",
  "description": "Get's rid of the bad X bullshit!",
  "permissions": [
    "<all_urls>",
    "tabs"
  ],
  "icons": {
    "48": "favicon.ico"
  },
  "content_scripts": [
    {
      "matches": [
        "*://twitter.com/*"
      ],
      "js": [
        "contentScript.js"
      ]
    }
  ],
  "browser_action": {
    "default_icon": "favicon.ico"
  },
  "web_accessible_resources": [
    "favicon.ico"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{7181b39c-fafb-43e5-b1f3-fc4271e60454}"
    }
  }
}