Examine source code of AO3 Word Replacer

{
  "manifest_version": 2,
  "permissions": [
    "storage"
  ],
  "content_scripts": [
    {
      "matches": [
        "https://archiveofourown.org/*"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "ao3-word-replacer@0nis",
      "strict_min_version": "91.0"
    }
  },
  "name": "AO3 Word Replacer",
  "version": "1.0.2",
  "description": "Replace words in AO3 fics with per-entry options"
}