Can the heights of all types of embeds be resized in ArcGIS StoryMaps?

Answer

Not all embeds can be resized. By default, in ArcGIS StoryMaps, embedded contents are often automatically resized to fit the frame, as there are no available settings to automatically allow the height of embeds to be adjusted. When media is embedded in a story map, it is displayed either as a card or interactive content.

Customizing the heights of embedded cards is not possible. Only the heights of interactive embeds can be adjusted. Refer to ArcGIS Blog: Enrich your stories with embedded web content to form a better understanding of the different ways to display embeds.

The story map below displays a dashboard embedded as a card with a fixed size.

Adjust the height of the interactive embeds using the iframe code

Note: 
This workflow is currently not applicable in mobile mode.

1. Log in to ArcGIS Online, and open ArcGIS StoryMaps.
2. In ArcGIS StoryMaps, navigate to the story and add the Embed block. Refer to ArcGIS StoryMaps: Add embeds for instructions. In this example, a dashboard is embedded.
3. In the Add web content window, on the Link tab, copy and paste the following iframe code and replace the <user_url> with the desired link:

<iframe width="100%" height="1180px" src="<user_url>"></iframe>

Note: 
Replace the height with the desired size by changing the pixel (px) value in the iframe code.

4. Click Add.

The story map below shows the dashboard embedded as an interactive embed with the height adjusted.