You are trying to create a mashup within an Embedded Component, but you're getting a pop up in UI Designer with the following error: The dragged mashup component can only be a inscreen mashup.
This happens because the mashup you're trying to create is of type URL with a viewstyle as "newWindow". This means it can be opened as an external link in a new window, which is why this is not allowed to be put into an Embedded component.
To be able to create a mashup within an Embedded Component you have to create a HTML mashup of type URL.
Mashup, Embedded Component, UI Designer, URL Mashup, HTML Mashup , KBA , AP-RC-UIF-XTS , UI Framework Cross Topics , Problem