TurnBasedStrategyCourse/Library/PackageCache/com.unity.2d.sprite@1.0.0/Editor/UI/SpriteEditor/PolygonChangeShapeWindow.uxml

<UXML xmlns:ui="UnityEngine.Experimental.UIElements" xmlns:uie="UnityEditor.Experimental.UIElements">
    <ui:VisualElement name="polygonShapeWindow" class="moduleWindow topLeft">
        <ui:Box name="polygonShapeWindowFrame">
            <uie:IntegerField name="labelIntegerField" class="labelIntegerField" label="Sides" value="0"/>
            <ui:VisualElement name="warning">
                <ui:Image name="icon"/>
                <ui:Label name="warningLabel" text="Sides can only be either 0 or anything between 3 and 128"/>
            </ui:VisualElement>
            <ui:Button name="changeButton" text="Change"/>
        </ui:Box>
    </ui:VisualElement>
</UXML>