I am running Xcode 11.3.1 on macOS 10.14. (I know, I'm a little behind, but the Mail bug in Catalina still makes me wary.) Lately editing in Xcode has slowed to a crawl. Activity Monitor shows the process com.apple.dt.SKAgent running consistently at over 170%. Keystrokes are often delayed by up to several seconds, and I had to turn off "suggest completions while typing" altogether, which further slows me down.
I've tried:
I've tried:
rebooting
closing any other open projects
quitting Xcode and deleting the "DerivedData" directory