Temporary shortcode block, when WordPress had a bug

shortcode2.php

<?php


add_action("init", function () {
    // Ob_start twice, intentionally
    ob_start();
?>
    <script type="module">
        <?php ob_start(); ?>
        wp.blocks.registerBlockType("temp/shortcode", {
            title: "Shortcode redux",
            icon: "shortcode",
            category: "common",
            attributes: {
                code: {
                    type: "string"
                }
            },
            edit: function(props) {
                function updateContent(event) {
                    props.setAttributes({
                        code: event.target.value
                    });
                }
                return wp.element.createElement(
                    "div", {
                        style: {
                            "padding": "1.5em",
                            "border": "1px solid currentColor",
                        }
                    },
                    [
                        "Shortcode",
                        wp.element.createElement("input", {
                            type: "text",
                            onChange: updateContent,
                            value: props.attributes.code,
                            style: {
                                "width": "100%",
                                "display": "block",
                                "box-sizing": "border-box"
                            }
                        })
                    ]
                );
            },
            save: function(props) {
                return null;
            }
        });
        <?php $code = ob_get_clean(); ?>
    </script>
<?php
    ob_get_clean();
    wp_register_script("temp-shortcode", false, ['wp-blocks', 'wp-element']);
    wp_add_inline_script("temp-shortcode", $code);
    register_block_type(
        'temp/shortcode',
        [
            'attributes' => [
                'code' => [
                    'type' => 'string',
                ],
            ],
            'editor_script_handles' => ['temp-shortcode'],
            'render_callback' => function ($attributes, $content) {
                return do_shortcode($attributes['code']);
            },
        ]
    );
});