when open menupopup, the spreadsheet will lost focus. but the menupopup is for spreadsheet, it should not lost focus.

If try to focus back to spreadsheet, the menupopup will disappear since spreadsheet regain focus, trigger onFloatUp event, it will close the menupopup

The current workaround is invoke js method
Spreadsheet.focus(false);//client side

//Server side can invoke by
Clients.evalJavaScript("zk.Widget.$('" + ss.getUuid() + "').focus(false);");

This js method won't really focus on spreadsheet DOM element, it only have focus "visual" effect