This was discovered in the bug JDK-8187772, where java runtime crashes if the user specifies their currency in the system preferences on macOS.

One way to resolve this is to honor that preference with the default locale set to xx-YY-u-cu-ZZZ, where ZZZ is the currency the user specifies. This should only happen if the HOST adapter is used, in order for the compatibility.

The currency override itself should be implemented with the JEP 8177568.