ModelProject/Library/PackageCache/com.unity.2d.animation@5.1.1/Editor/Assets/SkinningModule/BoneReparentWindow.uxml

<?xml version="1.0" encoding="utf-8"?>
<UXML xmlns:ui="UnityEngine.UIElements" xmlns:eui="UnityEditor.UIElements" xmlns:aui="UnityEditor.U2D.Animation">
  <aui:BoneReparentToolWindow name="BoneReparentToolWindow" picking-mode="Ignore">
    <ui:PopupWindow name="PopupWindow" text="Reparent Bones">
        <aui:BoneReparentToolView name ="BoneReparentToolView" />
    </ui:PopupWindow>
  </aui:BoneReparentToolWindow>
</UXML>