Examine source code of ShowSpeed

{
  "manifest_version": 3,
  "name": "ShowSpeed",
  "version": "1.8.0",
  "description": "Adds speed tier hover tooltips and EV creep tools to Pokemon Showdown teambuilder.",
  "browser_specific_settings": {
    "gecko": {
      "id": "showspeed@rashflygon.github.io",
      "strict_min_version": "121.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "permissions": [
    "storage"
  ],
  "host_permissions": [
    "*://play.pokemonshowdown.com/*",
    "*://smogtours.psim.us/*"
  ],
  "action": {
    "default_title": "ShowSpeed",
    "default_popup": "popup/popup.html",
    "default_icon": {
      "16": "icons/icon16.png",
      "32": "icons/icon32.png",
      "48": "icons/icon48.png",
      "128": "icons/icon128.png"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "*://play.pokemonshowdown.com/*",
        "*://smogtours.psim.us/*"
      ],
      "js": [
        "scripts/browser-api.js",
        "scripts/content.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "web_accessible_resources": [
    {
      "resources": [
        "scripts/injected.js",
        "scripts/browser-api.js"
      ],
      "matches": [
        "*://play.pokemonshowdown.com/*",
        "*://smogtours.psim.us/*"
      ]
    }
  ],
  "icons": {
    "16": "icons/icon16.png",
    "32": "icons/icon32.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  }
}