DefaultDockingManager does not load on Java 26 with NoClassDefFoundError for java.applet.Applet

[Captain-Chaos]

The JIDE libraries appear not to work on Java 26 due to a dependency on java.applet.Applet, which has been removed in that version of Java. The exception occurs when I try to instantiate a DefaultDockingManager with the following line:

dockingManager = new DefaultDockingManager(this, contentContainer);

You can see the line in context here: https://github.com/Captain-Chaos/WorldPainter/blob/90cb398123dc56016a8cda594d168cb305f67e11/WorldPainter/WPGUI/src/main/java/org/pepsoft/worldpainter/App.java#L2706

When I try to start WorldPainter on Java 26 now, it fails with the following stack trace:

java.lang.NoClassDefFoundError: java/applet/Applet
    at org.pepsoft.worldpainter.App.initComponents(App.java:2706)
    at org.pepsoft.worldpainter.App.<init>(App.java:192)
    at org.pepsoft.worldpainter.App.getInstance(App.java:1476)
    at org.pepsoft.worldpainter.Main.lambda$main$1(Main.java:493)
    at java.desktop/java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:323)
    at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:714)
    at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:693)
    at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:203)
    at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:124)
    at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:113)
    at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:109)
    at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
    at java.desktop/java.awt.EventDispatchThread.run(EventDispatchThread.java:90)
Caused by: java.lang.ClassNotFoundException: java.applet.Applet
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:580)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:502)
    ... 13 common frames omitted

I am using version 3.8.0 of the libraries, which is the latest as of this moment as far as I can see.