copyNames has been removed a long time ago, use showCopyOption instead.
ComputerSet/new.jelly was still using this deprecated field
@@ -37,7 +37,7 @@ THE SOFTWARE.
<l:breadcrumb title="${%New node}" />
<l:main-panel>
<j:invokeStatic var="slaves" className="hudson.slaves.NodeDescriptor" method="allInstantiable" />
- <n:form title="${%New node}" nameTitle="${%Node name}" copyTitle="${%Copy Existing Node}" copyNames="${it._slaveNames}"
+ <n:form title="${%New node}" nameTitle="${%Node name}" copyTitle="${%Copy Existing Node}" showCopyOption="${!empty(it._slaveNames)}"
descriptors="${slaves}" checkUrl="checkName" xmlns:n="/lib/hudson/newFromList" />
</l:main-panel>
</l:layout>
