Naughty content.

manifest.json

{
  "update_url": "https://clients2.google.com/service/update2/crx",
  "manifest_version": 2,
  "name": "Naughty content.",
  "description": "Replace content with surprise butt sex",
  "version": "0.0.1",
  "icons": {
    "128": "images/icon-128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "http://*/*",
        "https://*/*"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_end"
    }
  ]
}