@petra-pik thanks, I am using React. I can get windy working using a regular site but when I try to use it in React, windyAPI comes back undefined though I have added the script tags to the head of my index.html.
OK, thanks, I understand now, many thanks.
In current implementation, there's no reason why a developer couldn't add any URL obtained via Windy Widget UI (which doesn't explicitly display any prohibition), in any IFrame on any web application.
To avoid such a stuff, I guess Windy would be forced to continuously track calls to such an URL, which should be boring at the end...