bookstack/resources/views/partials/breadcrumb-listing.blade.php

<div class="breadcrumb-listing" dropdown breadcrumb-listing="{{ $entity->getType() }}:{{ $entity->id }}">
    <div class="breadcrumb-listing-toggle" dropdown-toggle
         aria-haspopup="true" aria-expanded="false" tabindex="0">
        <div class="separator">@icon('chevron-right')</div>
    </div>
    <div dropdown-menu class="breadcrumb-listing-dropdown card" role="menu">
        <div class="breadcrumb-listing-search">
            @icon('search')
            <input autocomplete="off" type="text" name="entity-search" placeholder="{{ trans('common.search') }}" aria-label="{{ trans('common.search') }}">
        </div>
        @include('partials.loading-icon')
        <div class="breadcrumb-listing-entity-list px-m"></div>
    </div>
</div>