newsupernova/vendor/magento/module-backend/view/adminhtml/templates/widget/grid/massaction.phtml

<?php
/**
 * Copyright © Magento, Inc. All rights reserved.
 * See COPYING.txt for license details.
 */

// @codingStandardsIgnoreFile

?>
<?= /* @escapeNotVerified */ $block->getSomething() ?>
<div id="<?= $block->getHtmlId() ?>" class="admin__grid-massaction">

    <?php if ($block->getHideFormElement() !== true):?>
    <form action="" id="<?= $block->getHtmlId() ?>-form" method="post">
    <?php endif ?>
        <div class="admin__grid-massaction-form">
    <?= $block->getBlockHtml('formkey') ?>
            <select
                id="<?= $block->getHtmlId() ?>-select"
                class="required-entry local-validation admin__control-select"
                <?= /* @escapeNotVerified */ $block->getUiId('select') ?>>
                <option class="admin__control-select-placeholder" value="" selected><?= /* @escapeNotVerified */ __('Actions') ?></option>
                <?php foreach ($block->getItems() as $_item):?>
                    <option value="<?= /* @escapeNotVerified */ $_item->getId() ?>"<?= ($_item->getSelected() ? ' selected="selected"' : '') ?>><?= /* @escapeNotVerified */ $_item->getLabel() ?></option>
                <?php endforeach; ?>
            </select>
            <span class="outer-span" id="<?= $block->getHtmlId() ?>-form-hiddens"></span>
            <span class="outer-span" id="<?= $block->getHtmlId() ?>-form-additional"></span>
            <?= $block->getApplyButtonHtml() ?>
        </div>
    <?php if ($block->getHideFormElement() !== true):?>
    </form>
    <?php endif ?>
    <div class="no-display">
    <?php foreach ($block->getItems() as $_item): ?>
        <div id="<?= $block->getHtmlId() ?>-item-<?= /* @escapeNotVerified */ $_item->getId() ?>-block">
            <?php if ('' != $_item->getBlockName()):?>
                <?= $block->getChildHtml($_item->getBlockName()) ?>
            <?php endif;?>
        </div>
    <?php endforeach; ?>
    </div>

    <div class="mass-select-wrap">
        <select
            id="<?= $block->getHtmlId() ?>-mass-select"
            class="action-select-multiselect _disabled"
            disabled="disabled"
            data-menu="grid-mass-select">
            <optgroup label="<?= /* @escapeNotVerified */ __('Mass Actions') ?>">
                <option disabled selected></option>
                <?php if ($block->getUseSelectAll()):?>
                    <option value="selectAll">
                        <?= /* @escapeNotVerified */ __('Select All') ?>
                    </option>
                    <option value="unselectAll">
                        <?= /* @escapeNotVerified */ __('Unselect All') ?>
                    </option>
                <?php endif; ?>
                <option value="selectVisible">
                    <?= /* @escapeNotVerified */ __('Select Visible') ?>
                </option>
                <option value="unselectVisible">
                    <?= /* @escapeNotVerified */ __('Unselect Visible') ?>
                </option>
            </optgroup>
        </select>
        <label for="<?= $block->getHtmlId() ?>-mass-select"></label>
    </div>

<script>
    require(['jquery', 'domReady!'], function($){
        'use strict';
        $('#<?= $block->getHtmlId() ?>-mass-select')
            .removeClass('_disabled')
            .prop('disabled', false)
            .change(function () {
            var massAction = $('option:selected', this).val();
            this.blur();
            switch (massAction) {
                <?php if ($block->getUseSelectAll()):?>
                case 'selectAll':
                    return <?= /* @escapeNotVerified */ $block->getJsObjectName() ?>.selectAll();
                    break;
                case 'unselectAll':
                    return <?= /* @escapeNotVerified */ $block->getJsObjectName() ?>.unselectAll();
                    break;
                <?php endif; ?>
                case 'selectVisible':
                    return <?= /* @escapeNotVerified */ $block->getJsObjectName() ?>.selectVisible();
                    break;
                case 'unselectVisible':
                    return <?= /* @escapeNotVerified */ $block->getJsObjectName() ?>.unselectVisible();
                    break;
            }
        });
    });
    <?php if (!$block->getParentBlock()->canDisplayContainer()): ?>
        <?= /* @escapeNotVerified */ $block->getJsObjectName() ?>.setGridIds('<?= /* @escapeNotVerified */ $block->getGridIdsJson() ?>');
    <?php endif; ?>
</script>
</div>