Xcode 8 hangs / unresponsive when opening storyboard

Question

I\'ve recently upgraded to Xcode 8 and updated my project to Swift 3. All worked fine for a little while. Storyboard loading has always been slow (even when still running Xcode

Answer 1

After deleting all sorts of things listed above, and restarting Xcode. The solution was to reboot the computer. Dumb I know, but somehow a resource was tied up in IB.