Track tabs open for same website for react.js app

trackTabsOpenWrapper.js

useEffect(() => {

    // define increment counter part
    const tabsOpen = localStorage.getItem('tabsOpen')
    console.log('tabsOpen', tabsOpen)
    if (tabsOpen == null) {
        localStorage.setItem('tabsOpen', 1)
    } else {
        localStorage.setItem('tabsOpen', parseInt(tabsOpen) + parseInt(1))
    }

    // define decrement counter part
    window.onunload = function (e) {
        const newTabCount = localStorage.getItem('tabsOpen')
        if (newTabCount !== null) {
            localStorage.setItem('tabsOpen', newTabCount - 1)
        }
    }
}, [])