title: Xcode 10.1 crashes on open due to detailAccentColor unrecognised
body: <p>So today while opening Xcode (Version 10.1 (10B61)) it installed some additional packages (unfortunately I don't know what). Then when it came to opening anything (existing project, creating a new project, creating playground) it crashed with error as posted below. </p>
  
  <p>I tried reinstalling Xcode, but the same error occurred.
  I'm using MacOS Mojave (version 10.14 (18A314k))</p>
  
  <p>And finally an error:</p>
  
  <pre><code>Process:               Xcode [2163]
  Path:                  /Applications/Xcode.app/Contents/MacOS/Xcode
  Identifier:            com.apple.dt.Xcode
  Version:               10.1 (14460.46)
  Build Info:            IDEFrameworks_Fall2018-14460046000000000~5
  App Item ID:           497799835
  App External ID:       828917606
  Code Type:             X86-64 (Native)
  Parent Process:        ??? [1]
  Responsible:           Xcode [2163]
  User ID:               501
  
  Date/Time:             2018-11-09 10:45:32.879 +0100
  OS Version:            Mac OS X 10.14 (18A314k)
  Report Version:        12
  Bridge OS Version:     3.0 (14Y664)
  Anonymous UUID:        4A06F9DE-9B81-BB53-A130-5A43E3077DDF
  
  
  Time Awake Since Boot: 5700 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:
  Sending newPlayground: to &lt;IDEApplicationCommands: 0x7ffea209fb20&gt; from (null)
  ProductBuildVersion: 10B61
  UNCAUGHT EXCEPTION (NSInvalidArgumentException): +[NSColor detailAccentColor]: unrecognized selector sent to class 0x7fff9fa73e28
  UserInfo: (null)
  Hints: 
    0: Sending newPlayground: to &lt;IDEApplicationCommands: 0x7ffea209fb20&gt; from (null)
    1: Sending createNewPlayground: to &lt;IDEWelcomeWindowController: 0x7ffea123e380&gt; from &lt;IDEWelcomeWindowHighlightButton: 0x7ffea13f21a0&gt;
  Backtrace:
    0   __exceptionPreprocess (in CoreFoundation)
    1   DVTFailureHintExceptionPreprocessor (in DVTFoundation)
    2   objc_exception_throw (in libobjc.A.dylib)
    3   +[NSObject(NSObject) doesNotRecognizeSelector:] (in CoreFoundation)
    4   ___forwarding___ (in CoreFoundation)
    5   _CF_forwarding_prep_0 (in CoreFoundation)
    6   -[DVTTheme activityViewDeterminateProgessIndicatorColor] (in DVTKit)
    7   -[IDEActivityProgressIndicatorLayer _updateProgressLayerColor] (in IDEKit)
    8   -[IDEActivityProgressIndicatorLayer reflectStyle] (in IDEKit)
    9   -[IDEActivityProgressIndicatorLayer setupLayers] (in IDEKit)
   10   -[IDEActivityProgressIndicatorLayer init] (in IDEKit)
   11   -[IDEActivityReportLayer init] (in IDEKit)
   12   +[IDEActivityReportLayer activityReportLayerForDisplayStyle:] (in IDEKit)
   13   -[IDEActivityView _buildReportLayerTree] (in IDEKit)
   14   -[IDEActivityView setupLayers] (in IDEKit)
   15   -[IDEActivityView setup] (in IDEKit)
   16   -[IDEActivityView setupOrTearDown] (in IDEKit)
   17   -[NSView _setWindow:] (in AppKit)
   18   -[NSView addSubview:] (in AppKit)
   19   -[NSToolbarItemViewer configureForLayoutInDisplayMode:andSizeMode:inToolbarView:] (in AppKit)
   20   -[NSToolbarView _layoutDirtyItemViewersAndTileToolbar] (in AppKit)
   21   -[NSToolbarView _syncItemSetAndUpdateItemViewersWithSEL:setNeedsModeConfiguration:sizeToFit:setNeedsDisplay:updateKeyLoop:] (in AppKit)
   22   -[NSToolbarView _noteToolbarLayoutChanged] (in AppKit)
   23   -[NSView _setWindow:] (in AppKit)
   24   -[NSView addSubview:] (in AppKit)
   25   -[NSTitlebarView addSubview:] (in AppKit)
   26   -[NSThemeFrame addTitlebarSubview:] (in AppKit)
   27   -[NSThemeFrame _showHideToolbar:resizeWindow:animate:] (in AppKit)
   28   -[NSWindow _showToolbar:animate:] (in AppKit)
   29   -[NSToolbar _show:animate:] (in AppKit)
   30   -[NSWindow setToolbar:] (in AppKit)
   31   -[NSWindow(IBNSToolbarFixes) ibSwizzledSetToolbar:] (in IDEInterfaceBuilderCocoaIntegration)
   32   +[IDEToolbarManager insertToolbarForToolbarDefinitionIdentifier:inWindow:] (in IDEKit)
   33   __45-[IDEWorkspaceWindowController windowDidLoad]_block_invoke (in IDEKit)
   34   -[NSObject(DVTObservingConvenience) _dvt_newObserverForKeyPath:options:owner:creationBacktrace:withHandlerBlock:] (in DVTFoundation)
   35   -[NSObject(DVTObservingConvenience) dvt_newObserverForKeyPath:options:withHandlerBlock:] (in DVTFoundation)
   36   -[IDEWorkspaceWindowController windowDidLoad] (in IDEKit)
   37   -[NSWindowController _windowDidLoad] (in AppKit)
   38   -[NSWindowController window] (in AppKit)
   39   -[IDEDocumentController _openUntitledWorkspaceDocumentAndDisplay:simpleFilesFocused:forSingleFile:editorDocumentURLOrNil:error:] (in IDEKit)
   40   -[IDEApplicationCommands newTemplateForTemplateKind:template:] (in IDEKit)
   41   -[IDEApplicationCommands newTemplateSkippingChooserIfPossibleForTemplateKind:] (in IDEKit)
   42   -[IDEApplicationCommands newPlayground:] (in IDEKit)
   43   -[NSApplication(NSResponder) sendAction:to:from:] (in AppKit)
   44   __37-[DVTApplication sendAction:to:from:]_block_invoke.99 (in DVTKit)
   45   DVTInvokeWithFailureHint (in DVTFoundation)
   46   -[DVTApplication sendAction:to:from:] (in DVTKit)
   47   +[IDECommandManager sendActionForCommandWithIdentifier:from:] (in IDEKit)
   48   -[NSApplication(NSResponder) sendAction:to:from:] (in AppKit)
   49   __37-[DVTApplication sendAction:to:from:]_block_invoke.99 (in DVTKit)
   50   DVTInvokeWithFailureHint (in DVTFoundation)
   51   -[DVTApplication sendAction:to:from:] (in DVTKit)
   52   -[NSControl sendAction:to:] (in AppKit)
   53   __26-[NSCell _sendActionFrom:]_block_invoke (in AppKit)
   54   -[NSCell _sendActionFrom:] (in AppKit)
   55   -[NSButtonCell _sendActionFrom:] (in AppKit)
   56   -[NSCell trackMouse:inRect:ofView:untilMouseUp:] (in AppKit)
   57   -[NSButtonCell trackMouse:inRect:ofView:untilMouseUp:] (in AppKit)
   58   -[NSControl mouseDown:] (in AppKit)
   59   -[NSWindow(NSEventRouting) _handleMouseDownEvent:isDelayedEvent:] (in AppKit)
   60   -[NSWindow(NSEventRouting) _reallySendEvent:isDelayedEvent:] (in AppKit)
   61   -[NSWindow(NSEventRouting) sendEvent:] (in AppKit)
   62   -[NSApplication(NSEvent) sendEvent:] (in AppKit)
   63   -[IDEApplication sendEvent:] (in IDEKit)
   64   -[NSApplication run] (in AppKit)
   65   NSApplicationMain (in AppKit)
   66   main (in Xcode)
   67   start (in libdyld.dylib)
  
  abort() called
  
  Application Specific Signatures:
  NSInvalidArgumentException
  </code></pre>