I have a KML that has points. These points have a popup that use HTML to display tables and images. When I convert the KML to a layer in ArcGIS Pro, the popup parses the HTML and CSS and displays as expected.

I've uploaded this layer to AGOL, and attempted to set the popup display to 'A custom attribute display' and simply put in the attribute tag.

However, it displays the HTML as text in the popup.

How can I get AGOL to display the HTML properly?