npm install --save vuex-persistedstate

import { createStore } from 'vuex'
import createPersistedState from 'vuex-persistedstate'
import App from '@/App'
import modules from '@/store'

const app = createApp(App)
const store = createStore({
  modules: modules, 
  plugins: [createPersistedState({storage: window.sessionStorage})]

})

app.use(store)
app.mount('#app')

参考：https://byceclorets.com/vue/vue3-vuex4-vuex-persistedstate/