Posters in the feed UX

[chrislegault]

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Description:
Sometimes posters in the feed take a decent amount of time to load. Some of mine an upward of half a second. Would it make sense to put in a loading state, or just a temporary display state (grey box) while the poster is loading?

[sachaw]

+1 for placeholder, much like feeds.

[trmcnvn]

/cc @JoshFabian might need a background color/image.