Hi
If the WPopupMenu menu is displayed with the WPopupMenu::popup ( WWidget * , Orientation orientation) method, the following error will appear no matter how the menu is closed:
Wt internal error; code: undefined, description: Cannot read properties of undefined (reading 'setHidden')
I tried two other versions of Method WPopupMenu::popup() and they worked fine.
Could it be related to this #13308?