Examine source code of Fxtwitter Link Rewrite

{
  "manifest_version": 2,
  "name": "Fxtwitter Link Rewrite",
  "version": "1.3",
  "description": "Rewrites links copied from twitter to be to fxtwitter.com for better unfurling in Discord and other places.",
  "content_scripts": [
    {
      "matches": [
        "*://x.com/*",
        "*://twitter.com/*"
      ],
      "js": [
        "fxtwitterRewrite.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "fxtwitterrewrite@qkleinfelter.com"
    },
    "gecko_android": {
      "strict_min_version": "113.0"
    }
  },
  "permissions": [
    "activeTab",
    "clipboardRead",
    "clipboardWrite"
  ]
}