...
The href and disabled attributes are still added/removed by AbstractLink as required. But no further mangling of markup is performed. org.apache.wicket.markup.html.link.DisabledLinkBehavior can be used to restore the pre-Wicket-7.x representation of disabled links with <em><span></span></em> (note that <em> and <span> swap their position though). If the old behavior is need it can be easily re-applied by using org.apache.wicket.markup.html.link.DisabledLinkBehavior.LinkInstantiationListener.
Button no longer silently ignores exceptions WICKET-5235
... when it renders its model into the value attribute.
Deprecated classes/methods/fields are removed WICKET-5201
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