This was a neat post from Joost de Valk back in July where he did some thinking out loud about the challenges of naming in Schema.org image standards to distinguish between featured and poster images on social networks:

I’ve been playing a lot with Schema and Social images recently and one thing has become clear: we need better naming of these images and we should probably improve the Schema.org image standards a bit. In this post I want to briefly discuss the different needs and my proposed (very simple) naming scheme.

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