Xcode is not responsive on startup for me when it is trying to reopen the previously open projects/files. This started once I opened a 1.2mb json file and I'm assuming Xcode is trying to parse it at open and doesn't finish. I killed Xcode, restarted, same thing. My advice to the Xcode team is if app is killed twice in a row to not open previously opened files on next start. I found a quick workaround: simply change the path of the projects/files that are troublesome, ex rename the file or its directory, then reopen Xcode - won't be able to open the file but continues loading.