It's also worth noting that the sidebar is hidden in the **mobile view**.

To see the sidebar customer need to click on the **minicart**.

This can confuse the customer when he will not be able to quickly find the **Place Order** button.

Hiding is implemented in the following file with `custom-slide` class:

`vendor/magento/module-checkout/view/frontend/web/template/sidebar.html`

```html
<div id="opc-sidebar"
     data-bind="afterRender:setModalElement, mageInit: {
    'Magento_Ui/js/modal/modal':{
        'type': 'custom',
        'modalClass': 'opc-sidebar opc-summary-wrapper',
        'wrapperClass': 'checkout-container',
        'parentModalClass': '_has-modal-custom',
        'responsive': true,
        'responsiveClass': 'custom-slide',
        'overlayClass': 'modal-custom-overlay',
        'buttons': []
    }}">

    <!-- ko foreach: getRegion('summary') -->
        <!-- ko template: getTemplate() --><!-- /ko -->
    <!--/ko-->

    <div class="opc-block-shipping-information">
        <!-- ko foreach: getRegion('shipping-information') -->
        <!-- ko template: getTemplate() --><!-- /ko -->
        <!--/ko-->
    </div>
</div>
```


----------


I made `VCT Place Order Sidebar (Button Lösung)` on Magento Marketplace module that implements this task for mobile view as well.