Cura adds strange helper outline

[nwild 0]

I want to print some very small piece (11.5x4x0.4mm).

It's  just a flat layer with some higher extrusion on one side (I attached some pictures).

 

Strange:

Cura adds some "line type helper" outline (cyan) around the piece and makes the thinner part on the edge now as thick as the higher extrusion.

I have no idea what that happens and I never had that before.

 

Any idea? It's not a raft/skirt/brim - I disabled all adhesion helpers.

[ahoeben 1,846]

Hard to tell from just the screenshots. Can you save a project? File -> Save as...