hi there 
now that the “photo card” has been deprecated, our twitter:image no longer displays as desired. we exclusively use portrait-oriented images and it seems twitter will crop these now (and crop them badly).
i reviewed the docs for the “Summary Card with Large Image” and didn’t see any mention of cropping or sizing rules that we are obviously breaking. further, when i validate my card, it displays as expected (see attached image)
are there plans to support portrait-oriented images? if not, are there hints we can provide to help you crop things better? (ex: center source image vertically, then crop off top and bottom as appropriate - vs. just taking the top portion).
thanks,
-matt