Add support to animated webp

[bkizzy]

1. Upload animated webp
2. Apply squoosh compression
3. Download webp

result: Only 1st frame of animated webp is preserved.

expected result: Entire webp is downloaded

[surma]

Yeah, we don’t support animation at all currently.

Not sure if we are ever gonna fix that considering the amount of work we’d have to go through to decode and show animated formats via wasm.

[kosamari]

Hi @bkizzy thanks for the feature suggestion! We had meeting today & concluded that this is nice-to-have-but-not-now feature.

We think this will be great addition but a lot to sort out (both UX & tech). We'll keep this issue open but probably not be able to get to it in foreseeable future.

[jakearchibald]

We might consider this once shssoichiro/oxipng#79 (or a similar tool) supports it

[surma]

I don’t think we will support animations any time soon for either WebP, AVIF or JPEG-XL.