diff --git a/Examples/Demo10.cpp b/Examples/Demo10.cpp
index 23c520d..533695c 100644
--- a/Examples/Demo10.cpp
+++ b/Examples/Demo10.cpp
@@ -220,6 +220,7 @@ int main()
 	myCellRange.setFormat( newCellStyle ); // assign the new format to the full range of cells
 
 	// ===== BEGIN cell borders demo
+	XLStyleIndex borderFormat = 0; // scope declaration
 	{
 		// create a new cell format based on the current C3 format & assign it back to C3
 		XLStyleIndex borderedCellFormat = cellFormats.create( cellFormats[ wks.cell("C7").cellFormat() ] );
@@ -227,7 +228,7 @@ int main()
 		wks.cell("C7") = "borders demo";
 
 		// ===== Create a new border format style & assign it to the new cell format
-		XLStyleIndex borderFormat = borders.create();
+		borderFormat = borders.create();
 		// NOTE: the new border format uses a default (empty) borders object to demonstrate OpenXLSX ordered inserts.
 		//       Using an existing border style as a template would copy the OpenXLSX default border style which
 		//       already contains elements in the correct sequence, so that inserts could not be demonstrated.
@@ -445,7 +446,10 @@ int main()
 		// output the value of the merge's top left cell
 		std::cout << "value of cell F6 by merge is \"" << wks.cell(topLeftRef) << "\"" << std::endl;
 	}
-	wks.cell("E4").setCellFormat( mergedCellFormat );
+	XLStyleIndex mergedCellFormatWithBorder = cellFormats.create( cellFormats[ mergedCellFormat ] );
+	if( false ) // enable this if you want to experiment with the borderFormat
+		cellFormats[ mergedCellFormatWithBorder ].setBorderIndex( borderFormat );
+	wks.cell("E4").setCellFormat( mergedCellFormatWithBorder );
 	wks.cell("J5") = "merged red range #2\n - hidden cell contents have been deleted!";
    wks.mergeCells("J5:L8", XLEmptyHiddenCells); // merge cells    with deletion of contents
 	wks.cell("J5").setCellFormat( mergedCellFormat );
diff --git a/README.md b/README.md
index 08ccac4..09ae48c 100644
--- a/README.md
+++ b/README.md
@@ -7,6 +7,9 @@ Microsoft Excel® files, with the .xlsx format.
 
 As the heading says - the latest "Release" that is shown on https://github.com/troldal/OpenXLSX/releases is from 2021-11-06, and severely outdated - please pull / download the latest SW version directly from the repository in its current state. Link for those that do not want to use ```git```: https://github.com/troldal/OpenXLSX/archive/refs/heads/master.zip
 
+## (aral-matrix) 07 April 2025 - Demo10: added a disabled use of borders with merged cells
+* enable Demo10 line 450 to experiment - but LibreOffice behaves weird (at least) with (diagonal) borders, so I have disabled this Demo functionality by default
+
 ## (aral-matrix) 24 March 2025 - XLStyles: XLFont fix attribute values underline, scheme, vertAlign
 * getters ```XLFont::underline, ::scheme, ::vertAlign```: fix default value to set for attribute val when tag doesn't exist
 * setter ```XLFont::setUnderline```: return correct "none" value for XLUnderlineNone from XLUnderlineStyleToString (was returning empty string)