Felt supports oEmbed, a standardized way of allowing rich embeds on third party sites like Notion or WordPress.
To achieve this, every map contains a line like this in the header following the standard oEmbed protocol:
<link rel="alternate" type="application/json+oembed" title="Global Human Settlement" href="<https://felt.com/oembed?format=json&url=https%3A%2F%2Ffelt.com%2Fembed%2Fmap%2FGlobal-Human-Settlement-5FzbIDg4RA9B5XnhuPnGgzC>">
That line contains a link with the form https://felt.com/oembed?format=json&url={FELT_MAP_URL}
which, when followed, returns a standard oEmbed response that can be used to embed the map in a page in the proper way:
{
"type": "rich",
"version": "1.0",
"title": "Global Human Settlement",
"html": "<iframe width="800" height="600" frameborder="0" title="Global Human Settlement" src="https: //felt.com/embed/map/Global-Human-Settlement-5FzbIDg4RA9B5XnhuPnGgzC"></iframe>",
"referer": "",
"thumbnail_url": "<https://d3a9fdbxbk3c9v.cloudfront.net/33fd3fdf-0e6d-49b3-83a4-a504d082668c.jpg>",
"cache_age": 3600,
"provider_name": "Felt",
"provider_resource": "<https://felt.com/embed/map/Global-Human-Settlement-5FzbIDg4RA9B5XnhuPnGgzC>",
"provider_url": "<https://felt.com>",
"thumbnail_height": 165,
"thumbnail_width": 220
}