When I open an existing project (following https://developer.apple.com/tutorials/swiftui/creating-and-combining-views) in Xcode, it crashes immediately with this "(tabController) should not be nil." error:
Code Block (tabController) should not be nil. Process: Xcode [11567] Path: /Applications/Xcode.app/Contents/MacOS/Xcode Identifier: com.apple.dt.Xcode Version: 12.3 (17715) Build Info: IDEFrameworks-17715000000000000~8 (12C33) App Item ID: App External ID: Code Type: ARM-64 (Native) Parent Process: ??? [1] Responsible: Xcode [11567] User ID: 501 Date/Time: 2020-12-19 01:09:44.783 +1100 OS Version: macOS 11.1 (20C69) Report Version: 12 Anonymous UUID: Sleep/Wake UUID: Time Awake Since Boot: 40000 seconds Time Since Wake: 310 seconds System Integrity Protection: enabled Crashed Thread: 0 Dispatch queue: com.apple.main-thread Exception Type: EXC_CRASH (SIGABRT) Exception Codes: 0x0000000000000000, 0x0000000000000000 Exception Note: EXC_CORPSE_NOTIFY Application Specific Information: ProductBuildVersion: 12C33 ASSERTION FAILURE in /Library/Caches/com.apple.xbs/Sources/IDEFrameworks/IDEFrameworks-17715/IDEKit/Workspace/IDEWorkspaceDocument.m:3270 Details: (tabController) should not be nil. Object: <IDEWorkspaceDocument: 0x11d5fdb20> Method: -commitStateToDictionary: Thread: <NSThread: 0x140628ff0>{number = 1, name = main} Open FDs: 38/7168 Hints: Backtrace: 0 -[IDEAssertionHandler handleFailureInMethod:object:fileName:lineNumber:assertionSignature:messageFormat:arguments:] (in IDEKit) 1 _DVTAssertionHandler (in DVTFoundation) 2 _DVTAssertionFailureHandler (in DVTFoundation) 3 -[IDEWorkspaceDocument showWindows] (in IDEKit) 4 -[DVTStateToken _copyStatefulObjectState] (in DVTFoundation) 5 -[DVTStateToken pushStateToRepositoryAndReturnError:] (in DVTFoundation) 6 -[DVTStateRepository _updateStateIfNeeded] (in DVTFoundation) 7 -[DVTStateRepository collectStateFromRegisteredObjects] (in DVTFoundation) 8 -[IDEWorkspaceDocument writeStateData] (in IDEKit) 9 28-[IDEWorkspaceDocument init]_block_invoke (in IDEKit) 10 -[DVTDelayedInvocation runBlock:] (in DVTFoundation) 11 NSFireDelayedPerform (in Foundation) 12 CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION (in CoreFoundation) 13 CFRunLoopDoTimer (in CoreFoundation) 14 CFRunLoopDoTimers (in CoreFoundation) 15 __CFRunLoopRun (in CoreFoundation) 16 CFRunLoopRunSpecific (in CoreFoundation) 17 RunCurrentEventLoopInMode (in HIToolbox) 18 ReceiveNextEventCommon (in HIToolbox) 19 _BlockUntilNextEventMatchingListInModeWithFilter (in HIToolbox) 20 _DPSNextEvent (in AppKit) 21 -[NSApplication(NSEvent) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] (in AppKit) 22 -[DVTApplication nextEventMatchingMask:untilDate:inMode:dequeue:] (in DVTKit) 23 -[NSApplication run] (in AppKit) 24 NSApplicationMain (in AppKit) 25 start (in libdyld.dylib) abort() called Application Specific Signatures: ((tabController)) != nil
Are there any workarounds?