OR

Add following code in di.xml

<type name="Magento\Quote\Model\Cart\CartTotalRepository">
    <plugin name="checkout_item_sidebar"
            type="SR\MagentoCommunity\Plugin\Quote\Model\Cart\CartTotalRepository" sortOrder="1"/>
</type>

app/code/SR/MagentoCommunity/Plugin/Quote/Model/Cart/CartTotalRepository.php

<?php
namespace SR\MagentoCommunity\Plugin\Quote\Model\Cart;

use Magento\Framework\Serialize\Serializer\Json;

class CartTotalRepository
{
    /**
     * @var Json
     */
    private $json;

    /**
     * DefaultConfigProvider constructor.
     * @param Json $json
     */
    public function __construct(
        Json $json
    ) {
        $this->json = $json;
    }

    public function afterGet(
        \Magento\Quote\Model\Cart\CartTotalRepository $subject,
        $quoteTotals
    ) {
        $quoteItems = $quoteTotals->getItems();
        $items = [];

        /**  @var \Magento\Quote\Model\Cart\Totals\Item $item */
        foreach ($quoteItems as $index => $item) {
            if ($options = $item->getOptions()) {
                $options = $this->json->unserialize($options);
                foreach ($options as $key => $option) {
                    if (isset($option['full_view'])) {
                        $options[$key]['full_view'] = html_entity_decode($option['full_view']);
                    }
                }
                $item->setOptions($this->json->serialize($options));
            }
            $items[$index] = $item;
        }

        $quoteTotals->setItems($items);
        return $quoteTotals;
    }
}

[Update]

Add following code in di.xml

<type name="Magento\Checkout\Model\DefaultConfigProvider">
    <plugin name="st_config_provider"
            type="SR\MagentoCommunity\Plugin\Checkout\Model\DefaultConfigProvider" sortOrder="1"/>
</type>

app/code/SR/MagentoCommunity/Plugin/Checkout/Model/DefaultConfigProvider.php

<?php
namespace SR\MagentoCommunity\Plugin\Checkout\Model;

use Magento\Framework\Serialize\Serializer\Json;

class DefaultConfigProvider
{
    /**
     * @var Json
     */
    private $json;

    /**
     * DefaultConfigProvider constructor.
     * @param Json $json
     */
    public function __construct(
        Json $json
    ) {
        $this->json = $json;
    }

    public function afterGetConfig(
        \Magento\Checkout\Model\DefaultConfigProvider $subject,
        array $result
    ) {

        $items = $result['totalsData']['items'];
        foreach ($items as $index => $item) {
            if (isset($item['options'])) {
                $options = $this->json->unserialize($item['options']);
                foreach ($options as $key => $option) {
                    if (isset($option['full_view'])) {
                        $options[$key]['full_view'] = html_entity_decode($option['full_view']);
                    }
                }
                $item['options'] = $this->json->serialize($options);
                $result['totalsData']['items'][$index] = $item;
            }
        }

        return $result;
    }
}