THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
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All setter methods in AbstractResource.ResourceResponse class now will return this instance for method chaining.
org.apache.wicket.markup.head.IHeaderItemWrapper is merged to IWrappedHeaderItem. WICKET-5366
IHeaderItemWrapper was a temporary class used to add a new method (#wrap(HeaderItem)) without breaking the APIs in Wicket 6.x.
The new method is moved its proper class - IWrappedHeaderItem.
Behavior changes
org.apache.wicket.request.Url#getQueryString WICKET-4664
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