CSS Performance deterioration in JavaFX21 (up to 10x)


With JavaFX21 I found in one of my applications a big performance degradation.
In the first case - Scrolling was super sluggish.

It’s most likely related to the following change:
ticket: https://bugs.openjdk.org/browse/JDK-8304959
PR: https://github.com/openjdk/jfx/pull/1070
commit: https://github.com/openjdk/jfx21u/commit/3fa02ee96a6dadbc20cacbf399a2d65df708eee1
(Tested with 21 and 22-ea+16)

JFXcentral:
Because the original case was closed source, it didn’t have a test application, but now I found it in another application.
(Actually, I think all applications are affected)

The issue can easily be replicated with JavaFX https://www.jfx-central.com/

GitHub: https://github.com/dlsc-software-consulting-gmbh/jfxcentral2
Run command:
./mvnw clean install; ./mvnw -P jpro -pl app javafx:run
Change JavaFX:
You can change the JavaFX version in the ./pom.xml
Statistics / DevMenu:
You can enable the developer menu with statistics at the top at
./app/pom.xml line 456 be setting develop to true: <option>-Ddevelop=true</option>
Stacktraces every 100ms:
You can uncomment the block about the Freezedetector at JFXCentral2App.java at line 293.

On my device, the stat “loadTimeFX” goes down from about 600 to 60 when switching from JavaFX21 to JavaFX20.