Autofill in merged cells splits them

Using Libreoffice Version: 5.3.1.2 in Linux

Trying to add a growing date to merged cells. I have tried both to add two consecutive dates and use the formula =“formercell”+1 but when I drag the fill handle, the merged cells splits.
Am I doing anything wrong?

Moving handle down, you also copying formating. If previous cell is not merged, next cell will split as this is controlled by formating. What you need to do is enter 11. 10. 2017 in A1 and then =A1 + 1 in B1. Now right click on B1 and click Copy. Select all cells where you need growing consecutive dates and do Right Shift + CTRL + V and select only Date and time. Click Ok.

Does it work?

I have the same problem.
Not only do not copy the cell format, it even jump a number if your initial cell is merged.2019-07-17 14-46-09.png