Selecting the attributes while creating new features using the Edit widget in ArcGIS Experience Builder becomes difficult if the Edit widget's window size is small and the attribute list is long.
This issue is not reproducible in the current version of ArcGIS Online and ArcGIS Experience Builder. If the issue persists, contact Esri Support Services.
解决办法
Click the Settings drop-down menu. The widget window now shows the scroll bar.
Edit the web experience and expand or maximize the widget window. Save and publish again.