Implement Rich Social Snippets for Social Media

[mediafinger]

You know, when you post a link and it expands to display a fat headline, a content snippet, an image and a link? Those things.

These should work at least on:

• [ ] Twitter
• [ ] Slack
• [ ] LinkedIn
• [ ] XING

and they should display different content depending if the link goes to:

• the usergroup's site
• an event
• a topic

Consider displaying the usergroup's logo if the event or topic does not have an image. Consider the language in which the snippet will be displayed.