Thank you @~Z~Man for paying your attention, I see that this component is available as a paid one in on SoftLab.
It should be in the Newsfeed page of User A's friends.
Simply I am suggesting the way of retweet/share in twitter/fb
what exactly should happen?
There is user A.
User A has a friend named user B.
User B made a post.
User A should be allowed to share the post of user B, you said.
WHERE exactly should that post be shared?