Can't replace block with empty file

I am just trying out the new Block definitions panel, which is a great improvement. It also makes me hopeful we will at some point see an outliner based on it.

Anyways, in our specific case I am replacing large numbers of blocks with meshes in them, with blocks with curves in them. A selection of blocks has to be replaced with an empty file though, since for them no curve would be placed.

If I switch the block definition to linked and select a file with nothing in it, it links the file, but still shows the geometry from the old file. Obviously it should show the contents of the linked file, which happens to be nothing.

Thanks for fixing!