Examine source code of PageFilter

{
  "manifest_version": 2,
  "name": "PageFilter",
  "short_name": "PageFilter",
  "version": "1.8resigned1",
  "description": "Auto hides elements on web pages containing specific user defined keywords.",
  "permissions": [
    "webRequest",
    "storage",
    "tabs",
    "<all_urls>"
  ],
  "applications": {
    "gecko": {
      "id": "mscard02@gmail.com"
    }
  },
  "icons": {
    "48": "icons/48.png",
    "96": "icons/96.png"
  },
  "options_ui": {
    "page": "options.html",
    "browser_style": true
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "pagefilter.js"
      ],
      "run_at": "document_end"
    }
  ]
}