Disallowed area or other setting only on Ultimaker 3

[jacobdobbratz 6]

If you select only one extruder, more specifically only extruder 2, then the build area changes. I can't see were in the definition file this is set up or how to replicate it. Could someone help me to understand how this is done and if it is possible to do it on my own definition files? I looked into both the Ultimaker 3 definition file as well as each extruder but there didn't seem to be a setting that differed from the Ultimaker 5 which doesn't change the build volume area when selecting different extruders. (Cura 4.11.0) The two images below show the desired results but I'd like to replicate them for a custom printer/extruder definition file.

[jacobdobbratz 6]

This does not require an answer anymore.
 

I understand now how this setting works. The "machine_nozzle_offset_x": is the source of the disallowed areas moving with each extruder being selected. The nozzle offset will be applied to whatever nozzle is active and if both are active in the settings then the disallowed areas will be copied/shifted  and overlaid for both heads.

[Smithy 1,088]

You were faster 🙂

The reason for the difference to the S5 is that the UM3 has not enough space for the head to get with both nozzles to all areas of the build plate.