Hello, we're working on fixing this issue. Thanks for informing us. You can temporarily turn off some visual effects in macOS (open System Preferences -> Accessibility --> Display --> Reduce transparency) or wait till our fix.
Hello again, we have prepared fix for this issue: 1) Revert "Reduce transparency" system preference to original value (if you had changed it to workaround the issue). Look my previous post how to find this option. 2) Update Toolbox to the latest version (2.5.1): open Toolbox --> 'Gear' button --> Check for Updates... and install the new version of Toolbox.