Unreal Engine Issues and Bug Tracker (UE-18200)

Description
Get nasty crash when performing a diff between two revisions on a BP uasset and then select a parent section that was modified, followed by a specific action performed on that section of the BP.
Callstack
"Assertion failed: Blueprint->SkeletonGeneratedClass != NULL [File:D:\BuildFarm\buildmachine_++depot+UE4-Releases+4.8\Engine\Source\Editor\Kismet\Private\BlueprintDetails

KERNELBASE
UE4Editor_Core!FOutputDeviceWindowsError::Serialize() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\core\private\windows\windowsplatformoutputdevices.cpp:95]
UE4Editor_Core!FOutputDevice::Logf__VA() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\core\private\misc\outputdevice.cpp:144]
UE4Editor_Core!FDebug::AssertFailed() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\core\private\misc\outputdevice.cpp:355]
UE4Editor_Kismet!FBlueprintVarActionDetails::PopulateCategories() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\editor\kismet\private\blueprintdetailscustomization.cpp:1080]
UE4Editor_Kismet!FBlueprintGraphActionDetails::CustomizeDetails() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\editor\kismet\private\blueprintdetailscustomization.cpp:2338]
UE4Editor_PropertyEditor!SDetailsViewBase::QueryLayoutForClass() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\editor\propertyeditor\private\sdetailsviewbase.cpp:512]
UE4Editor_PropertyEditor!SDetailsViewBase::QueryCustomDetailLayout() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\editor\propertyeditor\private\sdetailsviewbase.cpp:637]
UE4Editor_PropertyEditor!SDetailsViewBase::UpdatePropertyMap() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\editor\propertyeditor\private\sdetailsviewbase.cpp:1195]
UE4Editor_PropertyEditor!SDetailsView::PostSetObject() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\editor\propertyeditor\private\sdetailsview.cpp:612]
UE4Editor_PropertyEditor!SDetailsView::SetObjectArrayPrivate() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\editor\propertyeditor\private\sdetailsview.cpp:453]
UE4Editor_PropertyEditor!SDetailsView::SetObjects() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\editor\propertyeditor\private\sdetailsview.cpp:304]
UE4Editor_Kismet!SKismetInspector::MakeContextualEditingWidget() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\editor\kismet\private\skismetinspector.cpp:137]
UE4Editor_Kismet!SKismetInspector::UpdateFromObjects() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\editor\kismet\private\skismetinspector.cpp:657]
UE4Editor_Kismet!SKismetInspector::Tick() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\editor\kismet\private\skismetinspector.cpp:96]
UE4Editor_SlateCore!SWidget::Paint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\swidget.cpp:647]
UE4Editor_SlateCore!SPanel::PaintArrangedChildren() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\spanel.cpp:40]
UE4Editor_Slate!SSplitter::OnPaint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slate\private\widgets\layout\ssplitter.cpp:166]
UE4Editor_SlateCore!SWidget::Paint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\swidget.cpp:648]
UE4Editor_SlateCore!SPanel::PaintArrangedChildren() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\spanel.cpp:40]
UE4Editor_Slate!SSplitter::OnPaint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slate\private\widgets\layout\ssplitter.cpp:166]
UE4Editor_SlateCore!SWidget::Paint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\swidget.cpp:648]
UE4Editor_SlateCore!SPanel::PaintArrangedChildren() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\spanel.cpp:40]
UE4Editor_SlateCore!SPanel::OnPaint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\spanel.cpp:19]
UE4Editor_SlateCore!SWidget::Paint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\swidget.cpp:648]
UE4Editor_SlateCore!SPanel::PaintArrangedChildren() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\spanel.cpp:40]
UE4Editor_SlateCore!SPanel::OnPaint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\spanel.cpp:19]
UE4Editor_SlateCore!SWidget::Paint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\swidget.cpp:648]
UE4Editor_SlateCore!SCompoundWidget::OnPaint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\scompoundwidget.cpp:25]
UE4Editor_Slate!SBorder::OnPaint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slate\private\widgets\layout\sborder.cpp:94]
UE4Editor_SlateCore!SWidget::Paint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\swidget.cpp:648]
UE4Editor_Slate!SBox::OnPaint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slate\private\widgets\layout\sbox.cpp:169]
UE4Editor_SlateCore!SWidget::Paint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\swidget.cpp:648]
UE4Editor_SlateCore!SOverlay::OnPaint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\soverlay.cpp:97]
UE4Editor_SlateCore!SWidget::Paint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\swidget.cpp:648]
UE4Editor_SlateCore!SPanel::PaintArrangedChildren() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\spanel.cpp:40]
UE4Editor_Slate!SSplitter::OnPaint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slate\private\widgets\layout\ssplitter.cpp:166]
UE4Editor_SlateCore!SWidget::Paint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\swidget.cpp:648]
UE4Editor_SlateCore!SPanel::PaintArrangedChildren() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\spanel.cpp:40]
UE4Editor_SlateCore!SPanel::OnPaint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\spanel.cpp:19]
UE4Editor_SlateCore!SWidget::Paint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\swidget.cpp:648]
UE4Editor_SlateCore!SCompoundWidget::OnPaint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\scompoundwidget.cpp:25]
UE4Editor_Slate!SBorder::OnPaint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slate\private\widgets\layout\sborder.cpp:94]
UE4Editor_SlateCore!SWidget::Paint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\swidget.cpp:648]
UE4Editor_SlateCore!SCompoundWidget::OnPaint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\scompoundwidget.cpp:25]
UE4Editor_SlateCore!SWidget::Paint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\swidget.cpp:648]
UE4Editor_SlateCore!SPanel::PaintArrangedChildren() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\spanel.cpp:40]
UE4Editor_SlateCore!SPanel::OnPaint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\spanel.cpp:19]
UE4Editor_SlateCore!SWidget::Paint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\swidget.cpp:648]
UE4Editor_SlateCore!SPanel::PaintArrangedChildren() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\spanel.cpp:40]
UE4Editor_SlateCore!SPanel::OnPaint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\spanel.cpp:19]
UE4Editor_SlateCore!SWidget::Paint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\swidget.cpp:648]
UE4Editor_SlateCore!SOverlay::OnPaint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\soverlay.cpp:97]
UE4Editor_SlateCore!SWidget::Paint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\swidget.cpp:648]
UE4Editor_SlateCore!SCompoundWidget::OnPaint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\scompoundwidget.cpp:25]
UE4Editor_SlateCore!SWidget::Paint() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\swidget.cpp:648]
UE4Editor_SlateCore!SWindow::PaintWindow() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slatecore\private\widgets\swindow.cpp:1648]
UE4Editor_Slate!FSlateApplication::DrawWindowAndChildren() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:978]
UE4Editor_Slate!FSlateApplication::PrivateDrawWindows() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:1188]
UE4Editor_Slate!FSlateApplication::DrawWindows() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:941]
UE4Editor_Slate!FSlateApplication::Tick() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:1440]
UE4Editor!FEngineLoop::Tick() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\launch\private\launchengineloop.cpp:2388]
UE4Editor!GuardedMain() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\launch\private\launch.cpp:142]
UE4Editor!GuardedMainWrapper() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\launch\private\windows\launchwindows.cpp:126]
UE4Editor!WinMain() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\launch\private\windows\launchwindows.cpp:200]
Community References
UE 5.3 Sequencer issues/lack of knowledge?
Crash when selecting an action performed in a diff between two revisions in SVN
UE crashes often when trying to compile blueprints
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Cannot Reproduce
Component	UE - Gameplay - Blueprint Editor
Affects Versions	4.8
Target Fix	4.13
Fix Commit	3040565
Main Commit	3043181
Created	Jul 6, 2015
Resolved	Jul 7, 2016
Updated	Apr 27, 2018