ORIENT/modules/backend/layouts/form-with-sidebar.htm

<div class="layout responsive-sidebar">
    <div class="layout-cell">
        <!-- Breadcrumb -->
        <?php if ($breadcrumbContent = Block::placeholder('breadcrumb')): ?>
            <div class="control-breadcrumb">
                <?= $breadcrumbContent ?>
            </div>
        <?php endif ?>

        <div class="padded-container">
            <?= Block::placeholder('form-contents') ?>
        </div>
    </div>
    <div class="layout-cell width-300 form-sidebar control-scrollpanel">
        <div class="layout-relative">
            <div class="layout-absolute">
                <div class="control-scrollbar" data-control="scrollbar">
                    <div class="padded-container">
                        <?= Block::placeholder('form-sidebar') ?>
                    </div>
                </div>
            </div>
        </div>
    </div>
</div>