Compiled JS potentially mishandeling alpha channel

[stevenheffner]

Given this heic file 👇

https://static.elias.ink/resource/Elasticsearch-Logo-Color-V.heic

Convert it in this app (png) 👇

https://catdad-experiments.github.io/heic-app/

And you will see the alpha channel disappear 🪄 and be replaced with black

I also see the same thing when I use this CLI

https://github.com/catdad-experiments/heic-cli

And this code sandbox 👇

https://codesandbox.io/s/heic-conversion-forked-4sm6mr

All these examples use the compiled JS. I cannot confirm the libheif version they are using but I can confirm I'm seeing the same thing locally using

https://github.com/catdad-experiments/libheif-js

And it's using v1.15.1

I have confirmed that installing and using this library directly has no issues converting the image to a PNG with the proper alpha channel

Any idea whats going on here?

@catdad @farindk