KiCad build without 3D Connexion library

[Jan Wichmann]

Hello developers,

I am currently having a problem:
I would like to build Kicad from the current master without the 3D Connexion SPNAV library.

When I set the library in cmake from required to optional, I get lots of error messages such as:

Make Error in thirdparty/json_schema_validator/CMakeLists.txt:
[cmake]   Found relative path while evaluating include directories of
[cmake]   "nlohmann_json_schema_validator":
[cmake]
[cmake]     "SPNAV_INCLUDE_DIR-NOTFOUND"

Is it intentional that I can only build Kicad with the library, or is there a way to build it without this library again?

BR

Jan