What problem does this feature solve?

When conditionally rendering parent component, but still want to keep the children elements, I found the new fragment pattern could meet this need. When deliberately render fragment, I don't want vue to warn the extra props being passed since they might be used by custom-component. I don't know if there's a better way to achieve this.

<template>
  <component :is="condition ? 'custom-component' : 'v-fragment'" prop="prop">
    ...
  </component>
</template>

VFragment.vue

<template>
  <slot></slot>
</template>

What does the proposed API look like?

Something like fragmentWarning: false, sorry, can't come up with a better one.

Using inheritAttrs: false should suppress the warning:

https://jsfiddle.net/skirtle/637y4au8/

Does that cover your use case?

Yes, forgot the good old inheritAttrs, thanks!