Check and see what build you are using. We noticed this problem at our office under the Beta and build 815 that shipped on the disk. The downloadable
build 817 does not seem to share this problem.
matt johnson
archicad since 2004
imac 27, 4.2 GHz Intel i7, 16 GB RAM, radeon 575 4 GB, macOS 10.14.6
imac, 4.0ghz i7, 16gb ram, Radeon M9 390 2GB, OS X El Capitan