JavaFX does not build Media or WebKit native libraries by default, due to the lengthy build time (especially for WebKit), and dependencies on extra build tools. This makes it difficult for developers who want to build and test web or media applications. The javafx build will look in the ../caches directory (if present) or in the boot JDK, but this is inadequate. The ../caches directory needs to be populated manually and the boot JDK no longer has any sort of webkit or media libraries, much less up to date ones.

It would be a useful enhancement to optionally download media and webkit libraries from the latest openjfx EA build. This would be controlled by a new gradle property.

This was proposed by Jesper Skov on the openjfx-dev mailing list in this thread:

https://mail.openjdk.java.net/pipermail/openjfx-dev/2020-April/026023.html

And a preliminary (WIP) pull requests is here:

https://github.com/openjdk/jfx/pull/202