There are several known issues/limitations with the current implementation of merged cells:
- Thick border problem on merged cells
- If formatted gets white border.
- Problem with merged cell when scrolling
- Merged cells and freeze pane
- Merged cells, that are bigger than one Row and are combined whith hiderow, are changing there shape.
- Copy/fill and merged cells
- Moving cell reference onto merged cell
- Format painter doesn't copy merge info
- Merged cell is unmerged when shifting cells up in deletion
- Showpict in merged cell cut off when exported to pdf
- A merged cell causes "freeze" in Worksheet when moving down with shift key+down arrow.
These issues cannot be easily fixed, i.e. require re-implementation of the merged cells subsystem which per se is a bigger effort. #16557
