This did not work with java 13. To fix it, the sbt version has been
bumped to 1.3.3.
Then, the field EXIT_ON_CLOSE was not accessible anymore by JFrame. I used the same field from WindowConstants.
Also the commands in the README to start the scripts did not work anymore. So I changed the README commands.
This did not work with java 13. To fix it, the sbt version has been bumped to 1.3.3. Then, the field EXIT_ON_CLOSE was not accessible anymore by JFrame. I used the same field from WindowConstants. Also the commands in the README to start the scripts did not work anymore. So I changed the README commands.