Assortment of notes and stuff.
/Library/Java/JavaVirtualMachines/temurin-21.jdk.
~/opt).
Then:
$ cd ~/opt
$ unzip openjfx-21.0.9_osx-aarch64_bin-sdk.zip
Grab the maptool 1.18.6 JAR from GitHub.
Then do this (replace foo in /Users/foo with your username):
/Library/Java/JavaVirtualMachines/temurin-21.jdk/Contents/Home/bin/java \
--module-path /Users/foo/opt/javafx-sdk-21.0.9/lib \
--add-modules javafx.base,javafx.controls,javafx.fxml,javafx.graphics,javafx.media,javafx.swing,javafx.web \
--enable-native-access=javafx.media \
--enable-native-access=javafx.graphics \
-jar MapTool-1.18.6.jar