Examine source code of LIHKG Post Filter

{
  "manifest_version": 2,
  "name": "LIHKG Post Filter",
  "version": "0.4",
  "description": "Filters out threads with negative rating.",
  "icons": {
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://lihkg.com/*"
      ],
      "js": [
        "filter.js"
      ]
    }
  ]
}