sizes based on viewport-height unit

[tennox]

I have a use-case which I think is not currently possible:
A hero image with object-fit: cover that has full width a height of 88vh - so on portrait-orientation screens, using the width as indicator leads to a pixelated image.

I've tried different variations of sizes values, but setting a vh unit does not work:

<NuxtPicture class="block h-full w-full" :img-attrs="{ 'class': 'w-full h-full object-cover object-center-top' }"
    sizes="88vh lg:100vw" />

Might be enabled by #469 if I can set a custom value 🤔

Or is there a different way to achieve my goal?