When using Refined Alignment, a while line appears in Undo (normal behavior for a tool action) but:

1) Just one line, "not multiple line segments" as with other tools with each use of the Refined Alignement tool (note: that I can live with that and it could be as intended).

2) but that one white line will disappear and be replaced with the line from any of the other tools (W, E, T, S at least) which is a behavior different from any other tool (so I consider a bug).

Note: The same happens with the Align Protein to Density tool.