Map Viewer is unavailable in ArcGIS Pro Notebooks.

対処法

Refer to https://support.esri.com/en/Technical-Article/000024831 for more information. Update the version to ArcGIS API for Python 1.8.4 resolves this issue.

For ArcGIS API for Python 1.8.1 or later (ArcGIS Pro 2.6.x or later) 

For ArcGIS API for Python 1.8.1 or later, set the JSAPI_CDN environment variable to the following link, https://js.arcgis.com/4.15/. This process is different on Windows, Mac OSX, and Linux. Once the environment is set to variable, validate that Python can read it by running the following code: 

import os 

print(os.environ["JSAPI_CDN"]) 

The map widget displays successfully for all future notebooks if the above code runs without error and displays an HTTPS CDN.

再現の手順