If we told you even a year ago that an extremist group was making threats against Twitter Co-Founder Jack Dorsey and Other company workers you'd barely pay attention, let alone think that it was a serious situation. Unfortunately, after watching groups like ISIS make good on their threats, by threatening and then killing those that they believe are disrupting their plans, it's **w necessary to take everything seriously. When ISIS supporters posted a message on Sunday threatening Dorsey for deleting accounts connected to Muslim extremists that have used the social networking site to promote terrorism.