When working with Interface Builder...

If something goes wrong, just delete and start over.

Yesterday I was trying to create a complex layout that had several UIStackViews nested... The most that Xcode could handle? 3. After that, it just choke and wouldn't even load my Storyboard, even after ⌘+Q-ing it.

Then, connecting a view from a UITableViewCell to its class as an IBOutlet just made my app crash. I looked for wrong references, deleted them and added new ones... It didn't work until I deleted the whole prototype cell and rebuilt the layout, re-connected everything.