API: Wikipedia

API-Source: Wikipedia API is at https://www.mediawiki.org/wiki/API:Main_page
API-Example: https://en.wikipedia.org/w/api.php?format=json&action=query&prop=extracts&exintro=&explaintext=&formatversion=2&titles=Pope%20Francis
see Wikipedia: https://en.wikipedia.org/wiki/Pope_Francis
JCI-Syntax for free Plugin:
[jsoncontentimporter url=https://en.wikipedia.org/w/api.php?format=json&action=query&prop=extracts&exintro=&explaintext=&formatversion=2&titles=Pope%20Francis basenode=query]
{subloop-array:pages:-1}
{pages.title} {pages.extract}
{/subloop-array:pages}
[/jsoncontentimporter]

Example: We have a Problem with JSON here:
Either we got no JSON from the API. Or the basenode-parameter is not ok.
Switch on the Debugmode of the Plugin!
Switch to gutenberg-Blocks!
There the JSON Content Importer Block gives an easier way to use the JSON-APIs.
Or: Switch on the Debugmode by adding "debugmode=10" in the Shortcode.

If all is without success: Open ticket at wordpress.org please