Even though we build JavaFX binaries with JDK 18 as the boot JDK, the latest version of JavaFX still runs with JDK 11 (and is capable of being built using JDK 12 or later, and with some limitations, using JDK 11), although it isn't tested with older JDK versions.

In order for JavaFX to be able to use newer JDK features, such as records, switch expressions, text blocks, and so forth, we need to increase the minimum version of the JDK that can run the latest JavaFX. Additionally, there is an ongoing cost to keeping JavaFX buildable and runnable on older versions of Java, and very little reason to continue to do so.

This JBS issue proposed to bump the minimum version of the JDK needed to run JavaFX to JDK 17. This enhancement cannot be backported to any earlier version.