Whenever someone post a link of any thread in the forums, I'd like to see in the twitter card: Title of thread plus the first lines text of that thread. So I've tried to put this code in the SHOWTHREAD but it didn't work tho ..

Any ideas how to make that work? Like in this pic ignoring the image thumbnail.
<meta name="twitter:card" content="summary" />
<meta name="twitter:site" content="@mytwitteraccount" />
<meta name="twitter:description" content="{vb:raw thread.meta_description}" />
<meta name="twitter:title" content="{vb:raw thread.prefix_plain_html} {vb:raw thread.title}" />
--------- Edit ------------
Finally it's worked
I had to add these two codes in the showthread template at the end before </html>
Code:
<meta name="twitter:description" content="{vb:raw thread.meta_description}" />
<meta name="twitter:title" content="{vb:raw thread.prefix_plain_html} {vb:raw thread.title}" />