I have implemented twitter cards with deep linking, and it works before, in recent days, I just noticed that doesn’t work any more? At least not work in my iOS Twitter app.
I have checked the documentation again, nothing changed https://dev.twitter.com/cards/mobile
And a sample link: https://shou.tv/v/yjhtjmm
In the validator https://cards-dev.twitter.com/validator
INFO: Page fetched successfully
INFO: 23 metatags were found
INFO: twitter:card = summary_large_image tag found
INFO: Card loaded successfully