Excel Ribbon Button toggleButton: Shrink to fit (text)

This is a toggleButton button to switch "Shrink to fit" text on/off.

Issue: It does not refresh properly.

How do you build it to always "show" the active cells' state?

' -- XML

<customUI xmlns="http://schemas.microsoft.com/office/2009/07/customui" onLoad="LoadRibbon">
  <ribbon>
    <tabs>
      <tab id="Tabv3.1" label="TOOLS" insertAfterMso="TabHome">                  
        <group id="Group6" label="Alignment">
          <toggleButton id="ToggleButton1" 
                        label="Shrink to fit" 
                        imageMso="AsianLayoutCharacterScaling" 
                        size="large"
                        getPressed="ToggleButton1_Startup" 
                        onAction="ToggleButton1_OnAction"/>       
        </group>           
      </tab>
    </tabs>
  </ribbon>
</customUI>


' -- Standard Module

Option Explicit
Public RibUI As IRibbonUI

Sub LoadRibbon(Ribbon As IRibbonUI)
Set RibUI = Ribbon
    RibUI.InvalidateControl "ToggleButton1"
End Sub

' ToggleButton 1 Startup
Sub ToggleButton1_Startup( _
   ByRef control As IRibbonControl, _
   ByRef returnedVal)
   returnedVal = (Selection.ShrinkToFit = True)
End Sub

' ToggleButton 1 Click
Sub ToggleButton1_OnAction( _
   ByRef control As IRibbonControl, _
   ByRef pressed As Boolean)
   Select Case pressed
      Case True
            Selection.ShrinkToFit = True
      Case False
            Selection.ShrinkToFit = False
   End Select
End Sub


' -- ThisWorkbook

Private Sub Workbook_SheetActivate(ByVal Sh As Object)
    RibUI.InvalidateControl "ToggleButton1"
End Sub

• Using Workbook_SheetSelectionChange to trigger ribbon refresh

Microsoft documentation:

Workbook.SheetSelectionChange event (Excel)

' -- ThisWorkbook

Private Sub Workbook_SheetSelectionChange(ByVal Sh As Object, ByVal Target As Range)
    RibUI.InvalidateControl ("ToggleButton1")
End Sub