Adjusting color picker value for color structs within a structure crashes editor

Attempting to adjust the value of a color struct via the color picker in structures crashes the editor.

Frequency: 3/3

CrashReporter: [Link Removed]

Regression (Yes) issue (does not) occur in 4.11.2

1. Open Editor (any project)
2. Create new blueprint structure
3. Change variable to linear color struct
4. Select color to switch color value in color picker
5. Select new color in color picker

Results

Editor closes color picker, freezes, then crashes.

Expected

New color value selected, color picker remains open and shows representation of new color value.

MachineId:
EpicAccountId:89e014249c0a480eb18ea5b683d2eb3c

Fatal error: [Link Removed] [Line: 11]
Cast of nullptr to UserDefinedStructEditorData failed

UE4Editor_Core!FDebug::AssertFailed() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\core\private\misc\outputdevice.cpp:440]
UE4Editor_CoreUObject!CastLogError() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\coreuobject\private\templates\casts.cpp:12]
UE4Editor_UnrealEd!CastChecked<UUserDefinedStructEditorData const ,UObject>() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\coreuobject\public\templates\casts.h:203]
UE4Editor_UnrealEd!FStructureEditorUtils::GetVarDesc() [d:\build\++ue4+release-4.12+compile\sync\engine\source\editor\unrealed\private\kismet2\structureeditorutils.cpp:590]
UE4Editor_UnrealEd!FStructureEditorUtils::GetGuidForProperty() [d:\build\++ue4+release-4.12+compile\sync\engine\source\editor\unrealed\private\kismet2\structureeditorutils.cpp:800]
UE4Editor_Kismet!FDefaultValueDetails::OnFinishedChangingProperties() [d:\build\++ue4+release-4.12+compile\sync\engine\source\editor\kismet\private\userdefinedstructureeditor.cpp:193]
UE4Editor_Kismet!TBaseSPMethodDelegateInstance<0,FDefaultValueDetails,0,TTypeWrapper<void> __cdecl(FPropertyChangedEvent const & __ptr64)>::Execute() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\core\public\delegates\delegateinstancesimpl_variadics.inl:321]
UE4Editor_Kismet!TBaseSPMethodDelegateInstance<0,FDefaultValueDetails,0,void __cdecl(FPropertyChangedEvent const & __ptr64)>::ExecuteIfSafe() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\core\public\delegates\delegateinstancesimpl_variadics.inl:428]
UE4Editor_PropertyEditor!TBaseMulticastDelegate<void,FPropertyChangedEvent const & __ptr64>::Broadcast() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\core\public\delegates\delegatesignatureimpl_variadics.inl:921]
UE4Editor_PropertyEditor!FPropertyHandleBase::NotifyFinishedChangingProperties() [d:\build\++ue4+release-4.12+compile\sync\engine\source\editor\propertyeditor\private\propertyhandleimpl.cpp:2137]
UE4Editor_DetailCustomizations!FColorStructCustomization::OnSetColorFromColorPicker() [d:\build\++ue4+release-4.12+compile\sync\engine\source\editor\detailcustomizations\private\colorstructcustomization.cpp:268]
UE4Editor_DetailCustomizations!TBaseSPMethodDelegateInstance<0,FColorStructCustomization,0,void __cdecl(FLinearColor)>::ExecuteIfSafe() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\core\public\delegates\delegateinstancesimpl_variadics.inl:428]
UE4Editor_AppFramework!TBaseDelegate<void,FLinearColor>::ExecuteIfBound() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\core\public\delegates\delegatesignatureimpl_variadics.inl:612]
UE4Editor_AppFramework!SColorPicker::UpdateColorPick() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\appframework\private\widgets\colors\scolorpicker.cpp:768]
UE4Editor_AppFramework!SColorPicker::UpdateColorPickMouseUp() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\appframework\private\widgets\colors\scolorpicker.cpp:754]
UE4Editor_AppFramework!SColorPicker::ApplyNewTargetColor() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\appframework\private\widgets\colors\scolorpicker.cpp:734]
UE4Editor_AppFramework!SColorPicker::SetNewTargetColorHSV() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\appframework\private\widgets\colors\scolorpicker.cpp:714]
UE4Editor_AppFramework!TBaseSPMethodDelegateInstance<0,SColorPicker,0,void __cdecl(FLinearColor)>::ExecuteIfSafe() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\core\public\delegates\delegateinstancesimpl_variadics.inl:428]
UE4Editor_Slate!SColorWheel::ProcessMouseAction() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\slate\private\widgets\colors\scolorwheel.cpp:151]
UE4Editor_Slate!SColorWheel::OnMouseButtonDown() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\slate\private\widgets\colors\scolorwheel.cpp:43]
UE4Editor_Slate!<lambda_7097b900f0e4be30d80fb18f98c51ea0>::operator()() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:4518]
UE4Editor_Slate!FEventRouter::Route<FReply,FEventRouter::FBubblePolicy,FPointerEvent,<lambda_7097b900f0e4be30d80fb18f98c51ea0> >() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:215]
UE4Editor_Slate!FSlateApplication::RoutePointerDownEvent() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:4507]
UE4Editor_Slate!FSlateApplication::ProcessMouseButtonDownEvent() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:4465]
UE4Editor_Slate!FSlateApplication::OnMouseDown() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:4399]
UE4Editor_Core!FWindowsApplication::ProcessDeferredMessage() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\core\private\windows\windowsapplication.cpp:1518]
UE4Editor_Core!FWindowsApplication::DeferMessage() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\core\private\windows\windowsapplication.cpp:1850]
UE4Editor_Core!FWindowsApplication::ProcessMessage() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\core\private\windows\windowsapplication.cpp:745]
UE4Editor_Core!FWindowsApplication::AppWndProc() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\core\private\windows\windowsapplication.cpp:667]
user32
user32
UE4Editor_Core!FWindowsPlatformMisc::PumpMessages() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\core\private\windows\windowsplatformmisc.cpp:903]
UE4Editor!FEngineLoop::Tick() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\launch\private\launchengineloop.cpp:2729]
UE4Editor!GuardedMain() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\launch\private\launch.cpp:148]
UE4Editor!GuardedMainWrapper() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\launch\private\windows\launchwindows.cpp:126]
UE4Editor!WinMain() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\launch\private\windows\launchwindows.cpp:200]
UE4Editor!__scrt_common_main_seh() [f:\dd\vctools\crt\vcstartup\src\startup\exe_common.inl:264]
kernel32
ntdll