THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
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It was based on Swing APIs and many people complained about this. Use the new Tree component introduced in Wicket 6.0.0 instead.
Wicket.Window.unloadConfirmation has been removed WICKET-5246
In Wicket 6, Modal settings have been introduced, deprecating the old way of disabling unloadConfirmation. Please consider updating your JavaScript to remove calls to Wicket.Window.unloadConfirmation.
Dependency updates
All libraries on which Wicket modules depend are updated to their latest stable versions.
The most notable ones are:
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