What does this error mean: com.sun.glass.ui.mac.MacApplication lambda$waitForReactivation$6 WARNING: Timeout while waiting for app reactivation?

Question

Here are my systems details:

IntelliJ IDEA CE 2023.3 (Community Edition) Runtime version: 17.0.9+7-b1087.7 aarch64 VM: OpenJDK 64-Bit Server VM by JetBrains s.r.o. macOS 14.1.2

I created a new project using JavaFX and am trying to run the default application.java file to connect my SQL Database (in the same project), but I keep getting this error:

com.sun.glass.ui.mac.MacApplication lambda$waitForReactivation$6
WARNING: Timeout while waiting for app reactivation

The error shows up after I click run and the folder named, "java" shows up in the dock of my MacBook Air, but the GUI doesn't open up and then the folder closes after like 5 seconds and the error displays in IntelliJ. I've tried to troubleshoot it as much as I can, updating my JDK to 21.0.1, updating the IntelliJ application itself, updating my laptop to Sonoma 14.1.2, but nothing has seemed to work.

Please any insight would help!

Answer 1

Bug fix for WARNING: Timeout while waiting for app reactivation

This timeout issue on JavaFX application startup was caused by an incompatibility with JavaFX 21 (and perhaps other earlier JavaFX versions), which was introduced when Mac OS Sonoma (OS X 14) was released.

The bug was fixed in JavaFX 21.0.1.

The solution is to use JavaFX 21.0.1+ in your application.

This issue relates to the JavaFX version, not the JDK version.

Reference:

• JDK-8315657 Application window not activated in macOS 14 Sonoma.

---

Configuring the icon and name for the application is unrelated to the bug fix noted above. Information on how to do that is in the answer to:

• How can I change the app name from the default "Java" to something else with JavaFx on MacOs 14