The popup windows in AGOL only support certain HTML formatting tags, as described here. As a result, standard tags such as <sup> for superscripts are automatically removed when you close the map, even though they render just fine when you include them. For instance (and this is why this issue has come up), I'm am trying to setup a popup that includes the area of the selected polygon, which is represented in square metres. Because I can't use the <sup> tag, I have will have to use a work around like m^2, which does not look nearly as professional as saying m2 . Please include the functionality to use the standard HTML formatting tags in the popup window.