com.unity.perception/com.unity.perception/Editor/Randomization/Uxml/CategoricalParameterTemplate.uxml

<UXML xmlns="UnityEngine.UIElements" xmlns:editor="UnityEditor.UIElements">
    <Toggle label="Uniform" name="uniform"/>
    <VisualElement class="options-list-view">
        <ListView name="options"/>
    </VisualElement>
    <Button name="add-option" text="+ Add New Option" class="add-option-button"/>
</UXML>