I just tweeted a link to a blog and noticed that I hadn’t set a featured image. Therefore it uses a rather horrible default image (that I should get around to replacing).
I was under the impression that to fix this I had to delete the tweet, update the featured image for the blog post, and then repost my tweet, however, a colleague of mine showed me a trick to clear the Twitter cache and fix the original tweet.
So let me show you the steps that I go through to fix the issue.
After I have updated the featured image for my blog post, I go to the twitter card validator. I then enter the URL of the blog post in the Card URL box and press the Preview card button.
Using the above tool refreshes the cache of the the image that Twitter stores for that web page. Any tweet that links to that page will now display the new webpage preview, even tweets that have already been posted.
Sometimes I have found I need to press the Preview card button more than once to clear the cache.