The input field for your Organization URL in the Map Viewer Properties contains a regular expression to help with data validation. The expression is:
(http://|https://)(www.)?([a-zA-Z0-9]+).[a-zA-Z0-9]*.[a-z]{3}.?([a-z]+)?
Your URL does not meet these conditions.
Some options for you could be:
1. Ignore the errors in the UI. Your URL has already been successfully saved in the appinfo.json.
2. Edit the regular expression in the appschema.json for your app. This way, you can expand the conditions to include the format of your specific URL.
3. Remove the regular expression completely from the appschema.json.
I hope this helps,
Hannah