[3] リンク型 preview は、 プレビューを表します。
preview
Representative ImageThe representative image of the Object Construct is represented by the href attribute of an atom:link element, whose rel attribute value is "preview" and a whose type attribute value is an appropriate image media type.
Representative Image
The representative image of the Object Construct is represented by the href attribute of an atom:link element, whose rel attribute value is "preview" and a whose type attribute value is an appropriate image media type.
[4] Atom Activity Streams >>2
[5] app:preview
app:preview