When using inplace editing with combobox, the combobox drop-down button have the following behavior:

the drop-down button does not trigger when the combobox is in the "label" state. (the space used by the button still appear, but no behavior is available on it)
=> expected?

clicking on the drop-down button 3 times cause the combobox to loose its "editing" state and revert to "label" state.
Steps to reproduce:
Load the following page.
Select the combobox to activate edition.
Click 3 times on the combobox drop-down button
1st - open popup.
2nd - close popup
3rd - revert to label (no-edition) mode - expected : re-open popup.

<zk>
	<listbox hflex="min">
		<listitem>
			<listcell>
					<combobox value="default value" inplace="true">
						<comboitem>one</comboitem>
						<comboitem>two</comboitem>
						<comboitem>three</comboitem>
					</combobox>
			</listcell>
		</listitem>
	</listbox>
</zk>