merged shapes not splittable

In open office draw I used to merge complex line patterns with small line widths, then split the merged shape to get outlines of the spaces between lines.

With LibreOffice Draw when I Merge shapes they are not splittable. If I Combine them, the line ends become connected and the pattern is destroyed.

This is very disappointing.

Running version (x64)

Plese upload a sample file here.

If you treat objects with the function (context menu) Shape>Fusion (merge), they become one object. You cannot unmerge it again.

If you use the function “Group” instead, you can unmerge the objects afterwards as well as “Ungroup”.