Rene Ritchie on iMore:
If you use Tweetbot on the Mac, and Safari is your default web browser, clicking on a Twitter link—which the company insists on shortening to t.co—can result in errors, hangs, and general misery. Luckily, there’s a workaround that can help make the process seamless again.
There’s also a Safari Extension available that will do the same in case you aren’t using Tweetbot.
— Dan Loewenherz (@dwlz) January 6, 2016