- Currently, LinkedIn isn't one of the options for sharing. However, as you mentioned, you can copy the link to share it there. Since there are many social media providers out there, I don't think every single one can be supported. The supported ones include Google+, Facebook and Twitter which are the major social media providers.
As mentioned, there aren't a lot of people sharing on LinkedIn.
- Yes, if you are sharing directly, you will earn the badge. However, you must use the link from the 'Share' button as it includes your userid.
(share link) http://meta.stackexchange.com/q/289248/327561
(327561 is the userid).
(normal link) http://meta.stackexchange.com/questions/289248
(This won't work)