ArcGIS StoryMaps readers cannot save an image from a story by right-clicking the image and clicking Save image as.... In some cases, images must be saved by the story readers to be used accordingly. However, when saving an image, the error message, "Failed - Network error" is returned.
This is expected behavior in ArcGIS StoryMaps to protect images from being misused by other parties and to avoid copyright issues.
Instead of adding the image directly to the story, provide a URL of the image to let readers download or save the image from the specified location.
Note: Image can also be stored in any file storage provider such as Google Drive and OneDrive.
Readers can save the image from the provided URL.