I have been trying to add a save button to the AttributeInspector (just like here without the editor widget) of the Editor widget since our users don't find it intuitive to close the inspector to save edits. This approach requires accessing the AttributeInspector within the Editor widget, at which I have been unsuccessful. I have seen a few approaches such as:
attInspector = editor._attributeInspector; (here)
The documentation says: "The Editor widget provides out-of-the-box editing capabilities using an editable layer in a Feature Service. It combines the out-of-the-box TemplatePicker, AttachmentEditor, AttributeInspector and GeometryService to provide feature and attribute editing.". Is there a way to modify the AttributeInspector within the Editor widget?