Why is 8.90 duplicated in the name: libvtkCommonColor-8.90.so.8.90.0?
I would have expected libvtkCommonColor-8.90.so.0.
It is not just libvtkCommonColor following this naming scheme: libvtk*-8.90.so.8.90.0
Removing the VERSION "${VTK_VERSION}" line from vtk_module_build should fix this.
In any case, the repeat can be important. The two copies serve different purposes. The one in the SONAME ensures that 8.2 won’t accidentally get loaded. The last one ensures that 8.90.0 and 8.90.1 can be installed side-by-side (though there are other issues with this, so I’m fine with removing VTK’s usage of the VERSION argument).