Hi I struggled somewhat to get :web:test running with -PSTUB_RUNTIME.
The JVM kept crashing by what turned out to be missing media libraries (the failure message was hidden). I tried building with -PCOMPILE_WEBKIT=true, but it takes a terrible long time on my laptop. And did not in itself fix the problem. Frustrations and lost time was the only real outcome of this :) So I would suggest adding logic to the build file to allow something like: gradlew -PSTUB_RUNTIME_USE=15-ea+4 all test This should download org.openjfx:javafx-web and org.openjfx:javafx-media artifacts in the specified version. Then unpack the shared libraries to a build folder, and make them availble via the STUB_RUNTIME logic. Plus an addition to the CONTRIBUTING.md documenting this. I would be happy to help make and/or test the changes, but am only able to work on Linux. Thanks, Jesper