ET/Unity/Packages/YooAsset/Editor/AssetBundleDebugger/VisualViewers/DebuggerBundleListViewer.uxml

<ui:UXML xmlns:ui="UnityEngine.UIElements" xmlns:uie="UnityEditor.UIElements" editor-extension-mode="False">
    <ui:VisualElement name="TopGroup" style="flex-grow: 1; border-left-width: 1px; border-right-width: 1px; border-top-width: 1px; border-bottom-width: 1px; border-left-color: rgb(0, 0, 0); border-right-color: rgb(0, 0, 0); border-top-color: rgb(0, 0, 0); border-bottom-color: rgb(0, 0, 0); margin-left: 0; margin-right: 0; margin-top: 2px; margin-bottom: 1px; display: flex;">
        <uie:Toolbar name="TopBar" style="height: 25px; margin-left: 1px; margin-right: 1px;">
            <uie:ToolbarButton text="Bundle Name" display-tooltip-when-elided="true" name="TopBar1" style="width: 280px; -unity-text-align: middle-left; flex-grow: 1;" />
            <uie:ToolbarButton text="Ref Count" display-tooltip-when-elided="true" name="TopBar3" style="width: 100px; -unity-text-align: middle-left;" />
            <uie:ToolbarButton text="Status" display-tooltip-when-elided="true" name="TopBar4" style="width: 120px; -unity-text-align: middle-left;" />
        </uie:Toolbar>
        <ui:ListView focusable="true" name="TopListView" item-height="18" virtualization-method="DynamicHeight" style="flex-grow: 1;" />
    </ui:VisualElement>
    <ui:VisualElement name="BottomGroup" style="height: 200px; border-left-width: 1px; border-right-width: 1px; border-top-width: 1px; border-bottom-width: 1px; border-left-color: rgb(0, 0, 0); border-right-color: rgb(0, 0, 0); border-top-color: rgb(0, 0, 0); border-bottom-color: rgb(0, 0, 0); margin-left: 0; margin-right: 0; margin-top: 1px; margin-bottom: 1px; display: flex;">
        <uie:Toolbar name="BottomBar" style="height: 25px; margin-left: 1px; margin-right: 1px;">
            <uie:ToolbarButton text="Using Assets" display-tooltip-when-elided="true" name="BottomBar1" style="width: 280px; -unity-text-align: middle-left; flex-grow: 1;" />
            <uie:ToolbarButton text="Spawn Scene" display-tooltip-when-elided="true" name="BottomBar2" style="width: 150px; -unity-text-align: middle-left;" />
            <uie:ToolbarButton text="Spawn Time" display-tooltip-when-elided="true" name="BottomBar3" style="width: 150px; -unity-text-align: middle-left;" />
            <uie:ToolbarButton text="Ref Count" display-tooltip-when-elided="true" name="BottomBar4" style="width: 100px; -unity-text-align: middle-left;" />
            <uie:ToolbarButton text="Status" display-tooltip-when-elided="true" name="BottomBar5" style="width: 120px; -unity-text-align: middle-left;" />
        </uie:Toolbar>
        <ui:ListView focusable="true" name="BottomListView" item-height="18" virtualization-method="DynamicHeight" style="flex-grow: 1;" />
    </ui:VisualElement>
</ui:UXML>