Clicking the GameMode Override dropdown in the World Settings tab crashes the editor

Clicking the GameMode Override dropdown in the World Settings tab crashes the editor. Also occurs with any of the sub-options for the GameMode. Does not appear to occur if there is not already an existing GameMode placed (for example, in a new Blank Project). Does not occur if a change is made in the GameMode Blueprint itself, and thereafter the crash does not occur when making changes in the World Settings either.

No Crash Report is generated on Windows, and the log simply cuts off. Log attached.
Crashing on Mac generated this Crash Report: [Link Removed]

Reproduced in 4.8.1 and Main (//depot/UE4/Promotable-CL-2598974). This is a regression: did not occur in 4.7.6 or 4.8.0.

UPDATE: This no longer occurs in Main (//depot/UE4/Promotable-CL-2601051). Please identify the fix CL for hotfix inclusion.

Workaround: Select the gameMode in the Content Browser, and next to the "GameMode Override", use the arrow button to use that asset.

1. Open a new Third Person template project
2. Open the World Settings tab
3. Click the GameMode Override dropdown

Result:
Crash, no Crash Reporter

UE4Editor-Core.dylib!FTextFormatHelper::Format(FText const&, int, TBaseDelegate<FFormatArgumentValue const*, FString const&, int>, TSharedPtr<FTextHistory,()
UE4Editor-Core.dylib!FText::FormatInternal()
UE4Editor-Core.dylib!FText::Format()
UE4Editor-CoreUObject.dylib!LoadPackageInternal()
UE4Editor-CoreUObject.dylib!ResolveName()
UE4Editor-CoreUObject.dylib!StaticLoadObjectInternal()
UE4Editor-CoreUObject.dylib!StaticLoadObject()
UE4Editor-UnrealEd.dylib!FEditorClassUtils::GetClassFromString()
UE4Editor-UnrealEd.dylib!FGameModeInfoCustomizer::GetCurrentGameModeClass()
UE4Editor-DetailCustomizations.dylib!TBaseSPMethodDelegateInstance<true, FGameModeInfoCustomizer, (ESPMode)0, UClass const* ()>::Execute()
UE4Editor-PropertyEditor.dylib!SPropertyEditorClass::GetDisplayValueAsString()
UE4Editor-PropertyEditor.dylib!TBaseSPMethodDelegateInstance<true, SPropertyEditorClass, (ESPMode)0, FText ()>::Execute()
UE4Editor-Slate.dylib!TAttribute<FText>::Get()
UE4Editor-Slate.dylib!FTextBlockLayout::ComputeDesiredSize()
UE4Editor-Slate.dylib!STextBlock::ComputeDesiredSize()
UE4Editor-SlateCore.dylib!SWidget::CacheDesiredSize()
UE4Editor-SlateCore.dylib!SWidget::SlatePrepass()
UE4Editor-SlateCore.dylib!SWidget::SlatePrepass()
UE4Editor-SlateCore.dylib!SWidget::SlatePrepass()
UE4Editor-SlateCore.dylib!SWidget::SlatePrepass()
UE4Editor-SlateCore.dylib!SWidget::SlatePrepass()
UE4Editor-Slate.dylib!PrepassWindowAndChildren(TSharedRef<SWindow,()
UE4Editor-Slate.dylib!FSlateApplication::DrawPrepass(TSharedPtr<SWindow,()
UE4Editor-Slate.dylib!FSlateApplication::PrivateDrawWindows(TSharedPtr<SWindow,()
UE4Editor-Slate.dylib!FSlateApplication::DrawWindows()
UE4Editor-Slate.dylib!FSlateApplication::Tick()
UE4Editor-UnrealEd.dylib!TickSlate(TSharedPtr<SWindow,()
UE4Editor-UnrealEd.dylib!FFeedbackContextEditor::ProgressReported()
UE4Editor-Core.dylib!FFeedbackContext::UpdateUI()
UE4Editor-CoreUObject.dylib!LoadPackageInternal()
UE4Editor-CoreUObject.dylib!ResolveName()
UE4Editor-CoreUObject.dylib!StaticLoadObjectInternal()
UE4Editor-CoreUObject.dylib!StaticLoadObject()
UE4Editor-UnrealEd.dylib!FEditorClassUtils::GetClassFromString()
UE4Editor-UnrealEd.dylib!FGameModeInfoCustomizer::GetCurrentGameModeClass()
UE4Editor-DetailCustomizations.dylib!TBaseSPMethodDelegateInstance<true, FGameModeInfoCustomizer, (ESPMode)0, UClass const* ()>::Execute()
UE4Editor-PropertyEditor.dylib!SPropertyEditorClass::GetDisplayValueAsString()
UE4Editor-PropertyEditor.dylib!TBaseSPMethodDelegateInstance<true, SPropertyEditorClass, (ESPMode)0, FText ()>::Execute()
UE4Editor-Slate.dylib!TAttribute<FText>::Get()
UE4Editor-Slate.dylib!FTextBlockLayout::ComputeDesiredSize()
UE4Editor-Slate.dylib!STextBlock::ComputeDesiredSize()
UE4Editor-SlateCore.dylib!SWidget::CacheDesiredSize()
UE4Editor-SlateCore.dylib!SWidget::SlatePrepass()
UE4Editor-SlateCore.dylib!SWidget::SlatePrepass()
UE4Editor-SlateCore.dylib!SWidget::SlatePrepass()
UE4Editor-SlateCore.dylib!SWidget::SlatePrepass()
UE4Editor-SlateCore.dylib!SWidget::SlatePrepass()
UE4Editor-Slate.dylib!PrepassWindowAndChildren(TSharedRef<SWindow,()
UE4Editor-Slate.dylib!FSlateApplication::DrawPrepass(TSharedPtr<SWindow,()
UE4Editor-Slate.dylib!FSlateApplication::PrivateDrawWindows(TSharedPtr<SWindow,()
UE4Editor-Slate.dylib!FSlateApplication::DrawWindows()
UE4Editor-Slate.dylib!FSlateApplication::Tick()
UE4Editor-UnrealEd.dylib!TickSlate(TSharedPtr<SWindow,()
UE4Editor-UnrealEd.dylib!FFeedbackContextEditor::ProgressReported()
UE4Editor-Core.dylib!FFeedbackContext::UpdateUI()
UE4Editor-CoreUObject.dylib!LoadPackageInternal()
UE4Editor-CoreUObject.dylib!StaticLoadObjectInternal()
UE4Editor-CoreUObject.dylib!StaticLoadObject()
UE4Editor-UnrealEd.dylib!FEditorClassUtils::GetClassFromString()
UE4Editor-UnrealEd.dylib!FGameModeInfoCustomizer::GetCurrentGameModeClass()
UE4Editor-DetailCustomizations.dylib!TBaseSPMethodDelegateInstance<true, FGameModeInfoCustomizer, (ESPMode)0, UClass const* ()>::Execute()
UE4Editor-PropertyEditor.dylib!SPropertyEditorClass::GetDisplayValueAsString()
UE4Editor-PropertyEditor.dylib!TBaseSPMethodDelegateInstance<true, SPropertyEditorClass, (ESPMode)0, FText ()>::Execute()
UE4Editor-Slate.dylib!TAttribute<FText>::Get()

Fix UE-51650

"Session Disconnected" UEFN

I am not able to find world outliner how to enable it?

Undefined sysmbol: typeinfo for AActor when cross-compile linux dedicated server on windows

Delay nodes occasionally don't fire the "Completed" output in a nativized build

How can i modify the param name in EQS node

Installer 4.10 failed with error code R-1603

How to achieve HLSL Multiple Render Target in Material blueprints?

Bonjour j'ai un petit problème c'est que je ne vois plus l'onglet "scability" pour changer les graphismes de uefn et j'ai pas trouvé l'option pour le faire revenir ?

Why does the REMOVE method of map container remove elements have memory leaks?