- environment: MacOS 10.14.5
- download VirtualBox 6.0.6 from https://www.virtualbox.org/wiki/Downloads
- run installer
- popup with title System Extension Blocked and text A program tried to load one or more system extensions that are incompatible with this version of macOS. Please contact “Oracle America, Inc.” for support. appears
- installation fails
- workaround is to install VirtualBox 6.0.4 from https://www.virtualbox.org/wiki/Download_Old_Builds_6_0