chromium/chrome/test/data/extensions/api_test/service_worker/messaging/connect_to_worker/send_message/manifest.json

{
  "name": "Port connect from tab to SW based extension",
  "version": "0.1",
  "manifest_version": 3,
  "description": "Tests long lived connection between tab and SW extension",
  "content_scripts": [{
    "matches": ["*://127.0.0.1:*/*"],
    "js": ["content_script.js"]
  }],
  "background": {"service_worker": "service_worker_background.js"}
}