THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
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The 'quirk' properties were mostly related to IE6/7 and old versions of Firefox browsers.
org.apache.wicket.request.resource.AbstractResource#flushResponseAfterHeaders() is removed WICKET-5392
This method was needed as a workaround for some old version of Firefox that had an issue with rendering images.
The flush of the headers caused problems with proper buffering of the response, e.g. when the response needs to be compressed.
Behavior changes
org.apache.wicket.request.Url#getQueryString WICKET-4664
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