18.104.22.168 and Later
The internally used JRE.framework was upgraded from version 1.2 to version 2.1.1. This might cause some compiler errors related to nullable data types and renamed class names. Given the error messages, the these kinds of errors should be easy to fix.
If the compiler complains about missing class names, this most likely is caused by the "Protocol", which was removed from interface names. Nullable return types might be not nullable any more.