It's hard to tell from the video if you're doubble clicking
Run this little macro to see exactly what the .Color for Brown is
Option Explicit
'Public Const cBrown As Long = 4626167
Sub Macro1()
Range("DM3").Select
MsgBox ActiveCell.Interior.Color ' unfilled cell
Range("DM5").Select
MsgBox ActiveCell.Interior.Color ' marked cell
End Sub
Capture.JPG
The double click event if pretty simple
Option Explicit
' one line version :-)
'Private Sub Workbook_SheetBeforeDoubleClick(ByVal Sh As Object, ByVal Target As Range, Cancel As Boolean)
' Target.Cells(1, 1).Interior.Color = IIf(Target.Cells(1, 1).Interior.Color = cBrown, 16777215, cBrown)
'End Sub
Private Sub Workbook_SheetBeforeDoubleClick(ByVal Sh As Object, ByVal Target As Range, Cancel As Boolean)
With Target.Cells(1, 1)
If .Interior.Color = cBrown Then
.Interior.Color = 16777215
ElseIf .Interior.Color = 16777215 Then
.Interior.Color = cBrown
End If
End With
End Sub