Experimental mesh value "thickness" not changeable

[jupp2000]

Thank you Andrea, i found it. I am getting to old for finding the knobs....

[cam3d]

Hi jupp2000

You can find the experimental thickness slider under the custom settings when setting up the mesh wizard (reference image attached).

[jupp2000]

Hi all!
I read somewhere on sketchfab that the experimental mesh value "thickness = 2" should avoid holes in leaves.
but i cannot change this value, it is always zero.
how do I do that?

Kind regards
Jupp2000