test/Library/PackageCache/com.unity.package-manager-ui@2.0.13/Editor/Resources/Templates/PackageGroup.uxml

<?xml version="1.0" encoding="utf-8"?>
<engine:UXML 
        xmlns:engine="UnityEngine.Experimental.UIElements" 
        xmlns:upm="UnityEditor.PackageManager.UI"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:schemaLocation="UnityEngine.Experimental.UIElements UIElementsSchema/UnityEngine.Experimental.UIElements.xsd
                            UnityEditor.PackageManager.UI UIElementsSchema/UnityEditor.PackageManager.UI.xsd">
    <engine:VisualElement name="groupContainerOuter">
        <engine:VisualElement name="headerContainer">
            <upm:ArrowToggle name="headerCaret"/>
            <engine:Label name="headerTitle"/>
        </engine:VisualElement>

        <engine:VisualElement name="groupContainer" />
    </engine:VisualElement>
</engine:UXML>