The subject guide has descriptions for JRE/COMPAT system property values. Those descriptions should be modified along with this change.

More specifically in the interrnationalization guide (https://docs.oracle.com/javase/9/intl/internationalization-enhancements-jdk-9.htm#JSINT-GUID-5ED91AA9-B2E3-4E05-8E99-6A009D2B36AF)

There are four distinct sources : four -> three
COMPAT represents the locale data that is compatible with releases prior to JDK 9. : remove this bullet.
java.locale.providers=HOST,SPI,CLDR,COMPAT (first example): remove ,COMPAT
java.locale.providers=CLDR,COMPAT,SPI (second example): remove ,COMPAT,SPI
To enable behavior that is compatible with JDK 8, set the java.locale.providers system property to a value with COMPAT to the left of CLDR. : remove this line
Before For Supported Locales, add the following paragraph:
See the "JEP 252: Use CLDR Locale Data by Default" for more detail.
making the above JEP title as a link to https://openjdk.org/jeps/252