The Editor widget is empty in ArcGIS Experience Builder

Description

When launching a web experience from ArcGIS Online, the Editor widget does not show any editable layers and returns the following error:

Error: 
No editable layers found.

When launching the web experience in Portal for ArcGIS, the widget is completely empty, as shown in the following image.

Cause

• All layers specified in the widget are not editable. The Editor widget uses layers from a web map referenced in the Map widget inserted into the web experience. Even if the web map is shared publicly, the layer it references must be editable for use.
• The user viewing the web experience has a Viewer role. The layer is non-editable to users with a Viewer role even if editing is enabled on the layer.

Solution or Workaround

Note:
The user interface for the workflows are similar in Portal for ArcGIS and ArcGIS Online.

• Allow edits on the layer. Refer to Portal for ArcGIS: Manage hosted feature layer editing for more information.
• With an administrator account, change the user role to allow edits. Refer to Portal for ArcGIS: Change member roles for instructions. For more detailed information on the capabilities of each user role, refer to Portal for ArcGIS: Member roles.

The following image demonstrates the Editor widget working as expected.