FoundryVTT script macro for turning dead NPCs into lootables, using fvtt-loot-sheet-npc-5e - works best with a CUB Triggler trigger for NPCs dropping to hp <= 0

turn_defeated_into_loot.js

(async () => {
    let defeated = canvas.tokens.placeables.filter(t => {
        return t.data.disposition === -1 && t.data.actorData.data?.attributes?.hp?.value <= 0
    });

    for (let token of defeated) {
        if (token.actor.data.type != 'npc')
            continue;

        let invalid = await token.getFlag(`world`,`lootyfied`) ? await token.getFlag(`world`,`lootyfied`) : false;
        if (invalid)
            continue;

        let newItems = token.actor.data.items.filter(item => {
            // Weapons are fine, unless they're natural.
            if (item.type == 'weapon') {
                return item.data.weaponType != 'natural';
            }
            // Equipment's fine, unless it's natural armor.
            if (item.type == 'equipment') {
                if (!item.data.armor)
                    return true;
                return item.data.armor.type != 'natural';
            }
            // Item type blocklist.
            // Less intuitive than an allowlist,
            // but permits unknown module items.
            return !(['class', 'spell', 'feat'].includes(item.type));
        });

        // Change sheet to lootable, and give players permissions.
        let newActorData = {
            'flags': {
                'core': {
                    'sheetClass': 'dnd5e.LootSheet5eNPC'
                },
                'lootsheetnpc5e': {
                    'lootsheettype': 'Loot'
                }
            },
            'items': newItems,
            [`permission.default`]: 2
        };
        // Add proper currency info to the new data, if the actor needs it.
        if (undefined == token.actor.data.data.currency || token.actor.data.data.currency.cp == 0 ) // should be an object, not a number
        {
            newActorData['data.currency'] = {
                'cp': { 'value': null },
                'ep': { 'value': null },
                'gp': { 'value': null },
                'pp': { 'value': null },
                'sp': { 'value': null }
            };
        }
        await token.actor.update(newActorData);
        await token.setFlag(`world`,`lootyfied`,true);
    }
})();

get the following error now

Error: You are accessing PlaceableObject#data which is no longer used and instead the Document class should be referenced directly as PlaceableObject#document. Deprecated since Version 10 Backwards-compatible support will be removed in Version 12