webm to wav on react

convert.js

const toWav = require('audiobuffer-to-wav')
const audioContext = new (window.AudioContext || window.webkitAudioContext)()
const fileReader = new FileReader()

function download(blob){
    const url = window.URL.createObjectURL(blob)
    const anchor = document.createElement('a')
    anchor.href = url
    anchor.download = 'audio.wav'
    anchor.click()
}

fileReader.onloadend = () => {
    const arrayBuffer = fileReader.result
    audioContext.decodeAudioData(arrayBuffer, (audioBuffer) => {
        const wav = toWav(audioBuffer)

        const blob = new window.Blob([ new DataView(wav) ], {
          type: 'audio/wav'
        })

        download(blob);
    })
}

fileReader.readAsArrayBuffer(blobFromReactMic)