The problem is that whenever I open a storyboard or xib file the Interface Builder shows empty black rectangles for everything, with this error message on top:
I can add views and edit their properties, but the Interface Builder cannot refresh nor render anything.An internal error occurred. Editing functionality may be limited.
I have the Interface Builder's log files in case that's helpful, here's the error message from the Log.txt file:
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ERROR:
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Encountered an error communicating with IBAgent-iOS. (Failure reason: IBAgent-iOS (-1) failed to launch): Failed to launch IBAgent-iOS via CoreSimulator spawn (Failure reason: Failed to spawn IBAgent-iOS on iPhone 8 (9D490435-8326-4332-B838-180C6905F9B5, iOS 14.4, Booted)): Invalid device state
Error Domain=com.apple.InterfaceBuilder Code=-1 "Encountered an error communicating with IBAgent-iOS." UserInfo={NSLocalizedFailureReason=IBAgent-iOS (-1) failed to launch, NSUnderlyingError=0x7faccf1ad110 {Error Domain=com.apple.CoreSimulator.SimError Code=405 "Failed to launch IBAgent-iOS via CoreSimulator spawn" UserInfo={NSLocalizedFailureReason=Failed to spawn IBAgent-iOS on iPhone 8 (9D490435-8326-4332-B838-180C6905F9B5, iOS 14.4, Booted), NSLocalizedDescription=Failed to launch IBAgent-iOS via CoreSimulator spawn, NSUnderlyingError=0x7face91a49d0 {Error Domain=com.apple.CoreSimulator.SimError Code=405 "Invalid device state" UserInfo={NSLocalizedDescription=Invalid device state}}}}, NSLocalizedRecoverySuggestion=Please check Console.app for crash reports for "IBAgent-iOS" for further information., NSLocalizedDescription=Encountered an error communicating with IBAgent-iOS.}