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In case you want to implement your own IAuthenticationStrategy, a utility class org.apache.wicket.util.cookies.CookieUtils
has been added.
Removed CompressedPackageResource
Since all modern java and web servers support compression of resources we dropped that feature from wicket. Usually servers not only support that feature but also are more flexible so there's no need for a redundant functionality that does not belong to a web framework but to the server itself.
Removed IComponentBorder
The interface has been removed since IBehavior can do exactly the same. MarkupComponentBorder has been migrated, which means you can add associated markup to the behavior. Markup which will surround the behavior's component.
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