Thanks @discourse the topic that’s referred from https://twitter.com/philipdurbin/status/868795340354400256 does have a YouTube video in the opening post, and I do recall reading of a case (not this forum) where the presence of a video in a Discourse topic caused a problem in a tweet, but I don’t think that’s the problem here.
https://twitter.com/opensrcdesign/status/864001489437642752 from two weeks ago refers to something other than an opening post by @pdurbin and this tweet appears OK, Twitter presents Philip’s avatar on Discourse.
Results of a few more test tweets a few minutes ago:
The likelihood of a black rectangle appearing when a tweet refers to a topic (not to a numbered post) in this forum suggests to me that there remains an issue, or combination of issues, with local admin settings.
In the related GitHub issue it was observed that something was extraordinarily large. Whilst that one thing may be no longer an issue, the first of the five screenshots above does suggest that a more appropriately sized image (not necessarily a logo, not necessarily square) should be applicable somewhere in the admin settings.
Cards Markup Tag Reference — Twitter Developers
Summary Card with Large Image — Twitter Developers
The Definitive Guide to Twitter Cards | AdParlor
@jdittrich sorry for returning to this topic (after the detour to GirHub) but my gut told/tells me that some Discourse staff expertise may be required and it’s easier to address
@discourse from here.