Add Data Widget fails to add GPX file. Add Data widget—Web AppBuilder for ArcGIS | ArcGIS indicates that in WAB 2.3, one should be able to "Drag" or "Add" a GPX file to a web map using the widget. That does not occur, instead, an error message "Generate Feature Error: Data upload to hosted server failed". This is on an instance hosted internally, deployed using WAB for Developers. I am able to add zipped shapefiles (any projection) as well as csv files. I have tried many GPX files, which work fine in DNRGARMIN and Basecamp, so the problem is not with the GPX file. Happens with multiple versions of Chrome, Firefox, and IE.