Steps to Reproduce

1. run the attached zul
2. expand the first node

Current Result

zk.wpd:48151 Uncaught TypeError: Cannot read property 'isClientRodEnabled' of null
at init.setVisible (zk.wpd:48151)
at Function._set2 (zk.wpd:12115)
at init.setter.func (zk.wpd:20680)
at init.zk.Widget.zk.$extends.set (zk.wpd:20708)
at create (zk.wpd:26158)
at create (zk.wpd:26170)
at create (zk.wpd:26170)
at mtAU (zk.wpd:26058)
at zkx (zk.wpd:26245)
at zkx_ (zk.wpd:26261)

Expected Result

• no error
• the treeitem named "invisible" is hidden

Workaround

• create treerow and treecell and call treerow.setVisible(false)