Okay, I think I’ve found the issue, but I’m still waiting for clarification from anyone who has expertise in this area. It appears that when you apply for whitelisting you are requesting approval for just one style of card. When I applied for the card I had the “large image” card selected, but since then had decided I wanted to use the small preview card instead. This seems to be the cause of my issue. When I switched my site back to large image cards, the validator said everything was working.
The problem now is that I seem to be stuck with large image cards. When I switched my site back to the small preview card meta data, I am unable to submit an approval for those style of cards. I just get an “internal error” listing or “not whitelisted” error.
So suggestions for Twitter are:
- The error messages need to be more clear (ie "You are not approved for this type of card).
- Once approved for one type of card, there is no method for applying to any other types of cards.
- Whitelisting should be universal. Once approved for a card, sites should be able to switch whenever they like, so this mess doesn’t happen again.