Moving set from nested Bard to parent results in broken set

[o1y]

Bug description

When moving a set from a nested Bard field into its parent Bard field, the moved set becomes unusable.

How to reproduce

Drag and drop a nested Bard Set into the parent Bard

Logs

Uncaught (in promise) TypeError: can't access property "filter", fields is undefined
    fields Fields.vue:15
    refreshComputed reactivity.esm-bundler.js:391
    get value reactivity.esm-bundler.js:1648
    unref reactivity.esm-bundler.js:1493
    get reactivity.esm-bundler.js:1499
    _sfc_render Fields.vue:26

Environment

6.2.4

Installation

Fresh statamic/statamic site via CLI

Additional details

No response