chromium/chrome/test/data/extensions/manifest_tests/content_script_execution_world.json

{
  "name": "ContentScriptsManifestTest.ExecutionWorld",
  "version": "0.1",
  "manifest_version": 3,
  "content_scripts": [{
    "matches": ["https://example.com/*"],
    "js": ["file.js"]
  }, {
    "matches": ["https://google.com/*"],
    "js": ["file.js"],
    "world": "MAIN"
  }, {
    "matches": ["https://gmail.com/*"],
    "js": ["file.js"],
    "world": "ISOLATED"
  }]
}