Image Custom URL Link to Wikimedia Not Work

Have downloaded to my WordPress Media Library a Wikimedia image and then used the Add Media function to add image to a post (Abigail Adams). Top of post.

I then set a custom URL to point to the Wikimedia page for this image that provides information on the image including that the image is in the Public Domain.

Custom URL https://commons.wikimedia.org/wiki/File:Abigail_Adams.jpg

The Problem: When one clicks on the image, only a small box with a question mark appears. I think the problem is related to the colon in the URL name (not sure). The URL functions normally outside of the WordPress custom link.

How can I get the custom URL to work?

The page I need help with: [log in to see the link]