In debug mode, my app runs perfectly, so I built it as a standalone package on B4J 9.8 with OpenJDK 14 and... nothing.
The run_debug shows
D:\Dropbox\Development\ISBNLookup\Objects\temp\build\bin>java.exe @release_java_modules.txt -m b4j/uk.dotchurch.ISBNLookup.main
main._process_globals...