I highly recommend against downloading chrome extensions from unvetted third parties especially those which interact with LinkedIn. They are a VERY common vector for Malware, either to scrape your own contact details, to scrape your connections, or to do any manner of shady things.

There is a long and deep history of LinkedIn related chrome extensions that I won't get into. Many are a violation of LI's TOS. Most have to do with Lead sourcing for sales organizations. A lot of LI information ends up getting resold on grey market sites. Just don't do it. The convenience isn't worth it.