Here is an issue I am having with YouTube thumbnails in Summary Cards. I hope that I am putting this in the right place.
My cards were validated and approved a couple or a few weeks ago, but, although YouTube thumbnails show up in the Card validator (and I think maybe, but I’m not sure, one may have shown up once in a tweet), they consistently do not show up in my Summary Cards when I tweet my posts. Here is an example:
On top of this, when the YouTube thumb does not show, the card does not even default to any other image—in a couple of instances it failed to show any image that was in the tweeted post, and in the example above it failed to show the default avatar that I have primarily to show up on the summary card where a post has no image in it. (That avatar has, by the way, shown up in the Twitter cards of posts that had no image or YouTube embed in them.)
It seems to me that in my obsessive googling for an answer to this I did notice that the question was asked by one or two other Twitter users, but I have not seen any answer. Anyone know what’s going on?