We have today released a compatibility hotfix for Dorico 2 for users running macOS 10.14, version 2.1.20. It is functionally identical to Dorico 2.1.10 except it uses an updated version of the Qt framework with fixes for the on-screen display of fonts.
If you are running macOS 10.13 High Sierra or earlier, you do not need to download this update.
The new build can be found here.