Hi,
I came across with this problem as well in my local installation of Portal for ArcGIS and managed to fix it.
you can solve this bug manually by going to the local library where the JS API is located at (....\arcgis_js_api\library\), there should be a library called xstyle and there should be a file there named css.js
In that file, search for the following text -
a&&"none"!=a
and replace it with -
a&&"none"!=a&&"normal"!=a
in the api library, there might be a second version of this file, so it's just best to run a texet search on all files under that api location.
Hope that helps.
Cheers,
Shay.
