Attempting to set new access control on resource results in "Error: Drop fails to drop appropriate thing!"

Bug

I see the error: Error: Error: Drop fails to drop appropriate thing! https://solid.github.io/solid-ui/src/icons/noun_98053.svg when I try to change the access control for a resource by adding "Add Everyone" to "Viewers.

Steps to recreate

1. I created a directory in my root solidcommunity.net pod called getting-started
2. I visited https://.solidcommunity.net/getting-started/
3. I clicked on the padlock and then on the first green plus icon
4. I drag and dropped the "Add Everyone" icon to the "Viewers" row.
5. The error was shown.

Additional context

Once, somehow, I managed to "Add Everyone" to the Viewers list but I was not able to recreate that.

Riproduci il flusso drag-and-drop del controllo degli accessi descritto nell’issue: crea una directory al livello radice, apri il relativo lucchetto e trascina “Add Everyone” su “Viewers”. Traccia la gestione dell’interfaccia utente del controllo degli accessi per il fallimento del rilascio; l’attività è completata quando l’azione termina senza l’errore segnalato e il permesso compare nell’elenco “Viewers”.