I have added this extension along with the OpenGraph extension. This extension does not load any Twitter Tags. The opengraph extension loads og tags minus the image tag. I have tried everything I know to do. Any help would be greatly appreciated at this point.
Topic on Extension talk:TwitterCards
Concerning the Twitter card, are you the owner of this extension? If not, can you share a link to your own TwitterCard extension and/or a link to the OpenGraph extension so we can have a look? Here is the TwitterCard extension I know of: Extension:TwitterCards.
I am talking about the Extension you linked to above. This extension seems to have no affect on my site and its not adding the twitter tag to the metadata. Also the OpenGraph extension I am talking about is Extension:OpenGraphMeta This extension seems to work minus the image tag. I have tried everything to get the image tag working for OpenGraph but nothing seems to make a difference.
Okay! Thanks so much for your reply. One thing to note is that the TwitterCards extension is incomplete and as you can see, it's under experimentation. As for the OpenGraph extension, I have never used it but if you can understand MediaWiki extension, then you can add that functionality (image tag) into the extension to fulfill what you want to do. But try getting in touch with both extension developers and work with them.
You can ask on #wikimedia-dev IRC channel on FreeNode, that's the power house of Wikimedia Developers. I am currently unstable but when I have time, I will try to give you some consistent help.