Assistant - Filter for Qt Quick Controls and Qt Quick Controls Styles not working

Using package RC1 from 16/06 on Ubuntu 11.10

In Qt Assistant
Open menu View->Toolbars->Filter toolbar

In the "Filtered by" combo box select QtQuickControls 5.1 (or QtQuickControlsStyles 5.1)

The Qt Quick Controls doc (resp. Qt Quick Controls Styles) documentation is not shown in the Contents panel. The documentation is there though, just not found when using the filter.

See attached screenshot.