On Thursday, just after 6pm Irish time, Eoghan McCabe put up a seven-word tweet: “I’m back at @intercom as CEO!” There were screenshots too of an email the 38-year-old had sent earlier to Intercom staff, a number that is approaching 1,000, setting out in more detail the reasons for his return. Just twenty minutes later I’m on a video call to McCabe. He is sitting in his living room in his home in California. Despite Zoom and the time difference, McCabe’s infectious energy about the company is evident. He founded the business in 2011 with three friends, and he led…