magento-test/app/code/Magento/MediaGalleryUi/Test/Mftf/ActionGroup/AdminOpenMediaGalleryFromPageNoEditorActionGroup.xml

<?xml version="1.0" encoding="UTF-8"?>
<!--
 /**
  * Copyright © Magento, Inc. All rights reserved.
  * See COPYING.txt for license details.
  */
-->

<actionGroups xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
              xsi:noNamespaceSchemaLocation="urn:magento:mftf:Test/etc/actionGroupSchema.xsd">
    <actionGroup name="AdminOpenMediaGalleryFromPageNoEditorActionGroup">
        <conditionalClick selector="{{CmsNewPagePageContentSection.header}}" dependentSelector="{{CmsNewPagePageContentSection.contentHeading}}" visible="false" stepKey="clickExpandContent"/>
        <waitForElementVisible selector="{{TinyMCESection.InsertImageBtn}}" stepKey="waitForInsertImageButton" />
        <scrollTo selector="{{TinyMCESection.InsertImageBtn}}" x="0" y="-80" stepKey="scrollToInsertImageButton"/>
        <click selector="{{TinyMCESection.InsertImageBtn}}" stepKey="clickInsertImage" />
        <!-- wait for initial media gallery load, where the gallery chrome loads (and triggers loading modal) -->
        <waitForPageLoad stepKey="waitForMediaGalleryInitialLoad"/>
        <!-- wait for second media gallery load, where the gallery images load (and triggers loading modal once more) -->
        <waitForPageLoad stepKey="waitForMediaGallerySecondaryLoad"/>
    </actionGroup>
</actionGroups>