Libre Office Writer crashes when merging table cells

This time I know for sure: I created a new ODT document, a table, added some data in the table cells.
When I want to merge 2 cells on a column everything is OK, BUT if I want to merge the NEXT 2 cells on the NEXT column, Writer crashes.(I chose not to recover, not to enter safe mode, and I will open my document in normal mode: I can do a single merge, cause at the next merge of the cells, Writer crashes again. And so on. Does someone else has this problem too?

Cross-posted to https://superuser.com/q/1315717/541756.