ADDITIONAL SYSTEM INFORMATION :
MacOS versions:
10.11.6 El Capitan
10.12.6 Sierra
10.13.1 High Sierra
10.14 Mojave

JDK:
1.8u121
1.8u144
1.8u162
1.8u181


A DESCRIPTION OF THE PROBLEM :
We have a single threaded JavaFX application operating as a plugin under a Netbeans-based IDE. We've noticed that when running our application on MacOSX and using MacOS Accessibility applications (i.e. Magnet, HyperDock, VoiceOver) in the background, our application hangs indefinitely either at start-up or after the first UI interactions. We have narrowed the deadlock behavior to the following: whenever we call setScene() from our application it gets called on the Swing thread while Accessibility applications also make calls on Swing threads. This results in blocking the event queue which then causes a deadlock.


CUSTOMER SUBMITTED WORKAROUND :
close all Accessibility apps from the Accessibility Panel

FREQUENCY : always