Sorry for posting in two threads, but I just saw this one and the topic seems to be the same, but more current. I’m also having this issue.
A couple of observations:
We often post using HootSuite, which shortens the URLs with ow.ly. That said, the preview tool still shows the summary card with ow.ly-shortened URLs.
Our product URLs are often quite long because they are SEO-optimized, for example:
They can be reached using a shorter format, for example:
In the preview tool, the shorter format works where the standard form does not (the input field cuts it off), even though the shorter form automatically redirects to the page at the standard form URL. Neither format works for actual tweets.
Any thoughts?