In an ArcGIS online webmap one can make a custom attribute display popup. This is quite a powerfull feature, even allowing HTML formating.
I was trying to access external content from this custom window. This works perfectly fine by maken a link, however I also want to embed the content in the pop-up window itself.
By switching the edit box to "View HTML source" I wrote the following HTML:
This works seems to work well. When doing an identify a popup is shown with the link (the first 2 lines) and the external content (from the embed in the last line).
So far so good.
However, then I save and exit the webmap,
When I return to the webmap or try to use the web map in a web application, the embed-tag has disappeard. Than only the link to the external website is shown, but the content is not embedded.
Can anyone help me with the following questions:
Why is this happening? What subset of HTML may be used in custom popup? Are there alternatives to retrieve external content from a URL and in some way embed that in the popup?
Thanks in advance.