In ArcGIS Web AppBuilder, the widgets in Header Controller are not visible if white color is selected for Style in Theme.

Workaround

1. Download the widget-icons-master.zip and extract it to the machine.
2. Open ArcGIS Web AppBuilder in the editing session.
3. Navigate to Widget.
4. Click Set the widgets in this controller.
5. Click the Configure this widget icon.
6. Click Change widget icon, browse through zip file widget-icons-master>darkgrey>widgets>"WidgetName">images and resize the icon.
7. Click OK > OK.

Schritte zur Reproduzierung