Maps and Apps Gallery web app fails to launch from the ArcGIS Online home page

Description

An organization can style their own ArcGIS Online home page by configuring the background image, banner, and featured content. In the featured content, the administrator can select a group to be featured on the home page up to 32 items to display. If a web app that is configured with the Maps and Apps Gallery template is shared to a group on an organization's home page in ArcGIS Online, the app fails to open with the following error message:

Error:   
Unable to open item.

Cause

As of March 2018, the Maps and Apps Gallery app has moved to the Mature phase of the ArcGIS Online Product Lifecycle. The app has been removed from the default Configurable Apps Gallery. For more information, refer to the following ArcGIS Blog post, Maps and Apps Gallery Moving to Mature Support Phase.

Solution or Workaround

Create the web app from the group page using the Minimal Gallery template, and select the group to be featured on the home page. The Minimal Gallery template provides an alternative to display maps, apps, and scenes of the featured content. For more information, refer to ArcGIS Online Help: Minimal Gallery.

For steps to feature the content of the selected group on the home page, refer to ArcGIS Online Help: Configure home page.

Note: 
Only the Administrator of the organization has the permission to edit the site.