next.js/test/development/app-dir/strict-mode-enabled-by-default/app/page.js

'use client'
import { useEffect, useState } from 'react'

let i = 0
export default function Page() {
  const [, forceUpdate] = useState(0)
  useEffect(() => {
    console.log('user:log', i++)
    forceUpdate()
  }, [])
  return <p>{i}</p>
}