We have installed Portal for ArcGIS 10.3 on Windows Server 2008.
I encounter the following problem:
I create a simple WebMap, e.g. just adding one layer (e.g. the ArcGIS server test service SampleWorldCities) to the basemap.
Then I create a Web application from this map selecting the Web AppBuilder. I leave everything to the default settings (Foldable Theme).
If I then press first the button of the Legend widget and afterwards the button of the Layer List widget (in the Header Controller), I get the following error (in a popup):
create widget error:
widgets/LayerList/Widget
Pressing the Layer List widget before the Legend widget or using the Tab Theme, everything works fine.
Thanks
Hilde