Help and explanation please: `Uncaught (in promise) RuntimeError: null function or function signature mismatch` + Code

I do not actually know what this error means on the language of this package, but I can provide you with a simple example where it appears and **breaks** the worker (meaning worker becomes unusable until a page reload).


Here is the video.

https://github.com/ffmpegwasm/ffmpeg.wasm/assets/109352196/0e88899b-d14a-4fc4-8937-ef68672d2d50

See the code below.

## Next 14.0.4

A simple mockup project I bootstrapped just to show the error in your package guys

```tsx
'use client'

import { FFmpeg } from '@ffmpeg/ffmpeg'
import { fetchFile, toBlobURL } from '@ffmpeg/util'
import { downloadZip } from 'client-zip'
import { useRef, useState } from 'react'

export default function HomePage() {
const [loaded, setLoaded] = useState(false)
const [isLoading, setIsLoading] = useState(false)
const ffmpegRef = useRef(new FFmpeg())

const load = async () => {
setIsLoading(true)
const baseURL = 'https://unpkg.com/@ffmpeg/core@0.12.6/dist/umd'
const ffmpeg = ffmpegRef.current
await ffmpeg.load({
coreURL: await toBlobURL(`${baseURL}/ffmpeg-core.js`, 'text/javascript'),
wasmURL: await toBlobURL(`${baseURL}/ffmpeg-core.wasm`, 'application/wasm'),
})
setLoaded(true)
setIsLoading(false)
}

const convertAndDownload = async (files: File[]) => {
const ffmpeg = ffmpegRef.current
const convertedFiles = await Promise.all(
files.map(async (song) => {
const key = song.size
const iName = key + '.mp3'
const oName = key + '.ogg'
await ffmpeg.writeFile(iName, await fetchFile(song))
await ffmpeg.exec(['-i', iName, oName])
const o = (await ffmpeg.readFile(oName)) as Uint8Array
return new File([o.buffer], song.name, { type: 'audio/ogg' })
})
)

const blob = await downloadZip(convertedFiles).blob()

const url = URL.createObjectURL(blob)
const a = document.createElement('a')
a.href = url
a.download = 'songs.zip'
a.click()
}

return (

{loaded ? (
{
const mp3Files = Array.from(e.target.files!)
convertAndDownload(mp3Files)
}}
/>
) : (
{isLoading ? 'loading...' : 'load'}
)}

)
}
```

If you ever encountered this error, please give your feedback and solutions. Thanks